The BSA A7-A10 Forum

Technical => A7 & A10 Engine => Topic started by: Mosin on 09.08. 2009 21:27

Title: What goes in this hole then?
Post by: Mosin on 09.08. 2009 21:27
I was out for a lovely ride on the A7SS this afternoon and all seemed to be going very well. A bit too well as it happens...

After about 45 miles I started to ascend a very steep incline (Hartside in Cumbria for those of you who know it) As I was going up with the engine working hard and running a bit hot, I noticed the power seeming to fail. It almost felt like dirty petrol or the points not being set quite right. I ended up in first gear really revving the engine hard just to prevent it from stalling. Then all of a sudden it cleared and I made it up to the cafe at the top. My friend who had been following me said that as I had been struggling he had noticed a bit of blue smoke coming out of the left hand tail pipe, but this had cleared when the power returned.

We had our cup of tea and toasted sandwitch and I decided to check the plugs and points before continuing. All seemes fine and the A7SS fired up first kick and off we went. After about 20 more miles exactly the same thing happened again, but this time I could not make any power in any gear and we were forced to stop at a very nice pub. I noticed that once again the bike appeared hot and seemed to be leaking a bit of oil from what looked like the rocker cover gasket, but this stopped as she cooled down and off we went again, this time on a big main road where I was able to maintain a constant speed which seemed to keep the engine cool and she performed faultlessly for a further 15 or so miles with no visible sign of any oil leaking at all. Unfortunately, I had to slow down to go through Carlisle and as I left the city the problems returned. This time much worse with no power and oil gushing out all around the rocker cover and possibly also the cylinder head. At this point I phoned the RAC and got recovered home.

This evening I cleaned things up as best I could and pulled the tank off to see if I could see where the leak was coming from. It was then that I discovered this hole (picture) in the top of the rocker box. It is about an inch across and threaded on the inside. Looking in Haynes, there is no mention of it or what should be filling it. So, if anyone can help me, I Could do with knowing:

The engine still seems to have good compression, and all the oil seems to have come from the region of the rocker box, but I have never experienced a failure such as this to result in such a drastic lack of power before. Any help anyone can give me would be most welcome.

Simon
Title: Re: What goes in this hole then?
Post by: a10gf on 09.08. 2009 21:47
Some previous owner made his own breather system ? By itself this cannot have any influence on engine power afaik, but you'll get some oil spraying out. I suppose you still have enough oil left in the tank, or did it run low, and thus got engine overheating ? But low oil cannot explain this:
Quote
Then all of a sudden it cleared and I made it up to the cafe
unless it was close to seizing.
Title: Re: What goes in this hole then?
Post by: rocket man on 09.08. 2009 22:46
that doesint look good youd be best off removing the rocker box  id get another
one you could always put a breather on the rear rocker box inspection cover
thats the best place for one but that hole shouldent be there
Title: Re: What goes in this hole then?
Post by: trevinoz on 09.08. 2009 23:03
It looks like someone has modified the rocker box to be similar to the Ariel Huntmaster which has a threaded plug in the top to aid the fitting of the pushrods when fitting the rocker box.
Trev.
Title: Re: What goes in this hole then?
Post by: alanp on 10.08. 2009 08:53
Ummm, is it possible that whatever was in the hole fell inside and jammed a valve or rocker temporarily? I'd take the rocker cover off to check.
Title: Re: What goes in this hole then?
Post by: LJ. on 10.08. 2009 09:06
Quote
Ummm, is it possible that whatever was in the hole fell inside and jammed a valve or rocker temporarily? I'd take the rocker cover off to check.

Good idea Alan, I think I'd also want to take off the rocker box cover, chuck it away too and fit one with no modifications. If your engine is correctly fettled then you should not need any sort of breather up there. Neither of my A10s have any top end breathers and both run fine.

Sort that top end, fill up with plenty of oil and do the route again and lets see how she performs again. Then we can sort out the other problems if they reoccur.

Give us a shout if your stuck for a cover I may be able to help.
Title: Re: What goes in this hole then?
Post by: cus on 10.08. 2009 11:00
Mosin,
I agree with the others about that hole, but that power lose going up the hill (under load) sounds to me like
the engine nipping up, (partial seizing), if you are loading up the bike fully advanced, try retarding it a bit &
see if it improves, thats if you have a manual R/A lever, otherwise you might want to check the timing etc.
I had a similar problem on a bike with a Boyer & a wiring short, it would alter the timing, when the bike cools
down the piston frees up.

regards, Cus
Title: Re: What goes in this hole then?
Post by: RichardL on 10.08. 2009 14:11
Well, rocker-covers don't, now, seem to be scarce, but someday they will be. I don't like the idea of discarding still-useful and no-longer-made parts. The hole is evidently threaded, if original appearance is not an issue, why not plug it with a nicely fit and decent appearing threaded plug and move on? One could also use it as the breather port if one chose to do so. Otherwise put it on eBay to see if someone can get use out of it. Even if it ends up on a rat rod it's better than the scrap pile.

Richard L.
Title: Re: What goes in this hole then?
Post by: a10gf on 10.08. 2009 14:30
Richard wrote:
Quote
why not plug it with a nicely fit and decent appearing threaded plug
Yes, make something nice and rounded, then polish it all.
Title: Re: What goes in this hole then?
Post by: LJ. on 10.08. 2009 15:21
With hindsight to what your saying Richard, I think your correct! The hole is threaded as you do say, I'm wondering if the thread is the same as the clutch spring adjusting hole on the primary chain case in which fitting the appropriate plug would still serve as the push rod fiddling hole, if that is what the hole was put there for in the first place.
Title: Re: What goes in this hole then?
Post by: rocket man on 10.08. 2009 20:59
you could make it into an ashtray if you do deside to plug the hole up
make sure its well sealed id be worried about it vibrating lose again
get another one then its one less hole to worry about there are plenty about at the moment
try ebay
Title: Re: What goes in this hole then?
Post by: RichardL on 10.08. 2009 21:08
Not to get religious, or nothin', but that's why God made Loctite.
Title: Re: What goes in this hole then?
Post by: Mosin on 10.08. 2009 21:32
Not to get religious, or nothin', but that's why God made Loctite.

Hmm, maybe that's where I have been going wrong then. My Loctite is made by a company called "Henkel". Just my luck, God obviously invented the stuff, but despite his divine wisdom, lacked the sense to patent his design and I end up with some cheap copy...


Anyway, to get back to the subject of my hole. I have found and purchased a new 'unholy' rocker cover on ebay and also bought some oil and a new set of gaskets, so as soon as they arrive I will get them fitted and see where I go from there. This evening I have removed the old 'holy' cover in readiness. I also took the liberty of removing the sump plug and on doing so, the entire tank of oil poured straight out of the sump. The anti-wet sump valve had previously been working fine, but it would appear not to be working at all now. Could this in some way have contributed to my woes?

Thanks for all your help so far guys. I was feeling really down about the hole thing yesterday, but your collective wisdom and support has left me feeling a bit more upbeat about it today. One day this hole thing will be just a bad memory...



Simon
Title: Re: What goes in this hole then?
Post by: a10gf on 10.08. 2009 21:36
Heads up, quite often "Problems are sources of knowledge".
Title: Re: What goes in this hole then?
Post by: LJ. on 10.08. 2009 21:40
Chin up Simon, its not all bad, you only have to fit it now! Do you have the special comb? can be done without... just.

Do make sure the tappets are undone so they are completely loose, dont make the mistake of tightening the cover down against the springs as your likely to damage the corner studs. There is a lot of spring pressure there. Give us a shout if your unsure of anything.

Good luck! You'll be riding in no time.  *smile*
Title: Re: What goes in this hole then?
Post by: Mosin on 10.08. 2009 21:51
Chin up Simon, its not all bad, you only have to fit it now! Do you have the special comb? can be done without... just.

Do make sure the tappets are undone so they are completely loose, dont make the mistake of tightening the cover down against the springs as your likely to damage the corner studs. There is a lot of spring pressure there. Give us a shout if your unsure of anything.

Good luck! You'll be riding in no time.  *smile*

I bought one of the comb things off ebay while I was at it. I figured that it was probably worth it or they wouldn't sell them would they? Thanks for the reminder about slackening off the tappets beforehand. I've never fitted anything like this before, but realistically, I think it'll be fine. I mean, what could possibly go wrong...?
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 10.08. 2009 22:06
Hi Mosin,
Two Thoughts!!!!
When reading the thread firstly I thought it sounded like there was some water in your BSA's carb, it would suck it through every so often and the power would return????
Then at the last posting you said that all the oil had worked its way to the sump!!!
How long has the bike been standing?
The smoke your friend following saw could be from excess oil in the crank case
This oil would also lead to the lack of power!
Now I think more than likely that you have a problem with the scavenging side of the oiling system!!
Also maybe the cap in the rocker box was missing for some time and only when there was excess oil in the engine did it leak there???
You should have heard the engine huffing and puffing if the plug was missing?????
My ?0.02 opinion
Regards
John O R
Title: Re: What goes in this hole then?
Post by: Mosin on 10.08. 2009 22:28
Hi Mosin,
Two Thoughts!!!!
When reading the thread firstly I thought it sounded like there was some water in your BSA's carb, it would suck it through every so often and the power would return????
Then at the last posting you said that all the oil had worked its way to the sump!!!
How long has the bike been standing?
The smoke your friend following saw could be from excess oil in the crank case
This oil would also lead to the lack of power!
Now I think more than likely that you have a problem with the scavenging side of the oiling system!!
Also maybe the cap in the rocker box was missing for some time and only when there was excess oil in the engine did it leak there???
You should have heard the engine huffing and puffing if the plug was missing?????
My ?0.02 opinion
Regards
John O R


The bike had only been standing for two or three days since it was last run.

It is possible that the plug had been missing for some time, but I had never noticed either the hole itself or any excessive gasping from that area, and I have spent plenty of time recently listening to it. So I am guessing that whatever was filling the hole was still there.
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 10.08. 2009 23:09
Hi again Mosin,
Theres no way that the bike should have wetsumped in a couple of days,
presumably this had not happened before???
Look carefully at the oil pickup in the sump, make sure its clear,(there is a ball bearing inside this)
was there any gunge on the sump filter?
Before you run the bike again, I would drain and clean out the oil tank
disconnect the oil pipes at the engine and check that they are clear and not collapsed inwards
I would also be sorely tempted to remove the timing cover and remove the oil pump and check the crankcase oilways, especially if you find any muck in the sump or oiltank
Regards
John
Title: Re: What goes in this hole then?
Post by: Mosin on 11.08. 2009 13:18
Hi again Mosin,
Theres no way that the bike should have wetsumped in a couple of days,
presumably this had not happened before???
Look carefully at the oil pickup in the sump, make sure its clear,(there is a ball bearing inside this)
was there any gunge on the sump filter?
Before you run the bike again, I would drain and clean out the oil tank
disconnect the oil pipes at the engine and check that they are clear and not collapsed inwards
I would also be sorely tempted to remove the timing cover and remove the oil pump and check the crankcase oilways, especially if you find any muck in the sump or oiltank
Regards
John

*Gulp* That all sounds a bit worrying. Especially as it has never wet sumped before.
Title: Re: What goes in this hole then?
Post by: Mosin on 13.08. 2009 15:49
This is all getting a bit daunting.

What I think I will do is sort out the rocker box first (I picked up a new one off ebay and have bought a new gasket set to go with it). Once all this is back together, I will have a look at the oil situation. The pipes too and from the oil tank are virtually new so it is unlikely that they will have collapsed. The oil tank doesn't need draining as it's empty now anyway! I think that I will fill it up with the old oil and leave it standing for a day or so with the sump plug out and a container under it just in case. If nothing comes out, I might replace the sump plug and have a go at starting it briefly. Am I right in thinking that if I do this and I can see the oil being pumped through in the tank that everything is working ok? If all goes well at this point I will divert my attention to the timing as suggested.

Does this sound like a reasonable plan or is there anywhere else I should be looking?

Simon
Title: Re: What goes in this hole then?
Post by: RichardL on 13.08. 2009 15:58
Looking back through this topic, I didn't see where anyone mentioned the possibility of a really bad ball check-valve behind the oil pump. Maybe I missed it.
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 13.08. 2009 23:10
Hi again,
Simon, from your previous message I take it that you have an aftermarket sump plate with a drain plug
While these are great, some lazy sods dont now bother to remove the sump plate every so often to clean the gauze filter sandwiched between it and the crank case!
This is a fine gauze and can  become blocked by crap, this will stop the scavenge side of the pump
returning the oil to the tank,
One time I saw a gauze blocked by engine oil additive, this is so gooey that it clung to the gauze and would not let the oil through!!!!!
Other than that your plan sounds OK, remember it will take a little time for the oil to get all around the engine and enough to gather in the sump for the scavenge pump to return,
Remember there will be bubbles of air in the return oil as the scavenge side has a greater capacity than the pressure.
I never reuse the oil drained from the sump, it is inevitable that some dirt has fallen into the drain tray from the under side of the bike!!!
Best of luck
John O R
Title: Re: What goes in this hole then?
Post by: Mosin on 16.08. 2009 15:29
Update:

I have now fitted my new rocker box (what a fiddle that was) and poured the old oil back into the bike. This is just a temporary arrangement until I get it sorted, I have some fresh ready to go in as soon as it is all fixed, but I didn't see much point in putting the expensive new stuff in while there was still the possibility that it may just end up all over the road.

Anyway, plugs in, tank back on and to my not inconsiderable amazement she fired up! I quickly checked the oil return in the oil tank and it seems to be pumping oil through fine which I believe means that the oil pump/lines etc must be ok?

I didn't ride the bike, but just allowed her to warm up. However, once warm, there was a noticeable amount of white smoke coming from the left hand exhaust. There was no smoke at all coming from the right hand pipe. Could this be something to do with the timing being out as previously suggested, or is it likely to be something more sinister?


Simon
Title: Re: What goes in this hole then?
Post by: bsa-bill on 16.08. 2009 16:08
'They all do that sir'

Well not all of them but many A10/7s do, it will clear after a couple of hundred yards or so, many theories as to why.
not sure myself just what it is (I suspect guides on mine)

All the best - Bill
Title: Re: What goes in this hole then?
Post by: Mosin on 16.08. 2009 16:19
'They all do that sir'

Well not all of them but many A10/7s do, it will clear after a couple of hundred yards or so, many theories as to why.
not sure myself just what it is (I suspect guides on mine)

All the best - Bill

My concern is that she never used to smoke from either pipe prior to the difficulties of last Sunday. However, I shall go and give her a quick run up the road now and see how I get on.

Simon
Title: Re: What goes in this hole then?
Post by: Mosin on 16.08. 2009 17:14
Ok, so I have now done a couple of miles on the old girl and the left hand cylinder is blowing white smoke worse than ever through the exhaust pipe. I also notice that there is quite a bit of oil on the left hand side of the cyliner, but I cannot see where it is coming from (certainly not the rocker box though with its lovely new gasket). My initial thought was that it must be a head or base gasket gone and that the left hand pot was over heating and nipping up, but that doesn't explain the fact that I still have pretty good compression on both sides. Or why all my oil drained out of the sump. How had it got there?

Confused and frustrated.

Simon

Title: Re: What goes in this hole then?
Post by: rocket man on 16.08. 2009 17:56
i think you should strip the engine down and see if there
is an internal problem cheak pistons and rings and valve
seats i wouldent run her again till you find the problem otherwise
you may be doing more harm than good as for the hole something might
 have dropped inside the rocker box
and may be still in there so i would cheak that first
as it seems youve only had the problems since you noticed the hole
good luck
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 16.08. 2009 20:44
Hi Simon,
Check that the breather from the bottom rear of the crankcase is blowing out ok, start the engine and you should be able to feel the puffs from the hole!
If the head gasket is leaking into the pushrod gallery there will be a lot of crankcase pressure and oil leaks
Unfortunately it looks as if you will have to strip down the top half of the engine at least
It still doesnt answer why the oil leaked down into the sump though?????
Have you checked that the breather on top of the oiltank is clear?
On the first photo you posted, the links for the head steady are missing, did you take them off for the photo?
Unless the timing was badly out on the left hand cylinder causing overheating / or burnt valves, I dont think timing is the root cause of your problems??
Regards
John O R
Title: Re: What goes in this hole then?
Post by: RichardL on 16.08. 2009 21:19
Simon,

And, once you get a look at that head gasket, check it for leakage paths between oilways and the cylinder (they would show as dark pathways). Considering other issues with your engine, it is very likely that the former mechanic (I don't recall that being you) did not thoroughly anneal the head gasket before putting the head on, then, did not torque the headbolts down to their proper tightness. Both topics, anealing and headbolt torque are good for about two hours of reading herein.


Having noted the above, there is still a good possibility that the problem is valve guides. Base gasket? Seems doubtful.

Gents-at-large, what is a good test to determine worn guides? Maybe, fill the ports with thin oil with the head off, wait some time for it to slowly seep through, quickly empty out the ports, then, find some way to exercise the valves to see what comes out? I really don't know and have never tried such a thing, so any known procedure would be good to learn.

Richard L.

Richard L.
Title: Re: What goes in this hole then?
Post by: Mosin on 17.08. 2009 22:34
Ok, it looks as though I am going to have to bite the bullet and take the head off.

This evening I was describing the symptoms in some detail to an elderly and knowledgeable friend of mine who also has an A7SS, and he seemed fairly sure that it sounded like a knackered piston ring. He suggested having a good look at the plugs and sure enough, the left hand one (the side that was smoking) was all oily but the right hand one appeared absolutely fine.

I am not looking forward to doing this.... Not one bit....

Title: Re: What goes in this hole then?
Post by: LJ. on 18.08. 2009 09:20
Quote
I am not looking forward to doing this.... Not one bit....

Sorry to hear of your problems Simon, but hey relax you'll be okay. Just take your time and report back here for further advice if need be. You obviously enjoy riding the A10 and will probably now be keeping the bike for a very long time to come, just put this all down to experience as in a few months you'll be wondering what all the fuss was about. You'll get there!
Title: Re: What goes in this hole then?
Post by: Mosin on 18.08. 2009 11:06
Many thanks for the support and all the guidance guys, it is much appreciated.

This may sound like a supid question, but is it possible to remove the head with the valves in situ without disturbing them, or do I need to take them out as well?



Simon
Title: Re: What goes in this hole then?
Post by: a10gf on 18.08. 2009 11:21
Your burden is getting lighter: the head goes of as one piece with all internals.

When your done and found your problem, reassembling top, just some fun aligning the 4 cam rods, you'll need the tool (http://www.a7a10.net/techpics/prodtool.jpg), tightening the bolts following the right procedure, then readjust tappets clearance. See the 'head' pages under tech and maintenance here (http://www.a7a10.net/BSAGoldenFlash.htm). More info: here (http://www.a7a10.net/forum/index.php?topic=454.0) & here (http://www.a7a10.net/forum/index.php?topic=1475.0). Check\replace the cylinder top & base gaskets.
Title: Re: What goes in this hole then?
Post by: RichardL on 18.08. 2009 12:47
A few extra tips that I have learned along the way and/or the hard way:

1. Removing the rocker box will be easier if the rear center cover stud is removed, thus avoiding the top frame member.
2. Let the stickyness of your gasket sealer hold the rocker-box base gasket to the box during replacement. (The tool will still get a bit goopy on removal.)

3. The tool comes out by sliding it forward and there is just enough space between front and rear rockerbox sections to, then, pull it out sideways.
3. Slacken the tappet adjusters so there is no force on the valves as the rocker box is tightened down.
4. When you're done using the comb of the tool to align the rods, use the other end (placed between head fins) as a platform to support the hex nuts (one at a time) as you work on getting them started on the front studs. Otherwise, this is nut-dropping nightmare (humor there, but not really intended).

Richard L.
Title: Re: What goes in this hole then?
Post by: Mosin on 20.08. 2009 20:19
OK guys, now I am flummoxed.

This evening I removed rockerbox, head and barrels. There was a lot of oil around the cylinder head, but the gasket appeared to be ok (see photo). When I got the barrels off, the piston rings all appeared to be intact. However, while the right hand piston is all clean and shiny, as you can see, the left hand one (the side that was smoking) is all streaky.

Any suggestions to what may have caused this or further diagnoses?

As always, many thanks.

Simon
Title: Re: What goes in this hole then?
Post by: a10gf on 20.08. 2009 20:43
Elimination method? Gap checking: when contracted, do you have a correct gap on all rings ? And are they moving freely or is anyone stuck. Remove rings (read a little about 'how to' before breaking one!) and insert into respective cylinder using a piston to push them in, and measure gap in different parts in the cylinder. If all seems ok, then move on. What's your piston to cylinder clearing?

The marks on the piston may be signs of oil starving, do you have the conrod with the extra oil hole near the bottom, pointing inwards towards the centre of the crankshaft. Is sludge trap clean. Piston, may be just a polish job to salvage, if the cylinder bore otherwise looks ok.

At least some ideas to start with. Next suggestions, please.
Title: Re: What goes in this hole then?
Post by: RichardL on 20.08. 2009 21:37
Maybe the gasket leaks, but can't tell very well. Guides must be considered a possible source as well, having found no broken rings.

Don't forget, anneal the new head gasket (or, maybe, the used one, but better new) before putting it back together. It's a bit hard to see the scoring of the piston and excessive oil in the combustion chamber as related, assuming the ring gaps, as A10gf has mentioned, are correct.

Repeating - Next suggestions, please.

Richard L.

IN THE PICTURE, I MEAN "OTHER SIDE OF THE GASKET."
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 20.08. 2009 22:59
Hi Simon,
A couple of things to check, as others have said re oil starvation,
Is the trough under the camshaft full of oil?
are there any scores on the cams or followers?
Have you removed the sump filter plate and gauze  yet?
Are there scores on the LH bore?

in one of the photos there is a lot of excess gasket goo on the primary case!
Is this the same goo that was used on the engine?
Excess goo can easily block oilways /gauzes etc

Look in the ports on the head and see if there is oil on the inlet valves/guides
also the same on the exhaust sides
Regards
John O R
Title: Re: What goes in this hole then?
Post by: trevinoz on 21.08. 2009 03:40
Looks to me like seize marks.
Trev.
Title: Re: What goes in this hole then?
Post by: cus on 21.08. 2009 05:43
Mosin,
I'd agree with that, looks like it's been nipping up, you mentioned in earlier posts that it was getting hot,
you might want to have a good look at your timing, do you have a manual or auto R/Advance?
I just re-built a bike & had 3 peice oil rings made, if you can access them where you are, it might be
worth doing,

regards, Cus
Title: Re: What goes in this hole then?
Post by: RichardL on 21.08. 2009 06:03
Gents,

Everyone is talking about the siezing up, but the observed running problem was white smoke, which is normally diagnosed as burning oil. Of course, whatever is causing the siezing needs to be fixed, but, it seems to me, the oil burning might be a separate issue. The siezing may have been one isolated occurance in the past.  However, we are not seeing the bores. Perhaps the left bore is scored enough to prevent the oil scraper from doing its job. Ipso-facto, burning oil.

Richard L.
Title: Re: What goes in this hole then?
Post by: cus on 21.08. 2009 07:23
Yeah, I think it probably wouldn't be bad advise, that now its apart to get those barrells looked at, maybe new pistons, rings, guides etc.


Cus
Title: Re: What goes in this hole then?
Post by: a10gf on 21.08. 2009 07:38
Quote
problem was white smoke
A little off topic, my experience with engines: black smoke = fuel, blue smoke = oil, white smoke = ...water !

ps: has become quite a topic. I mentioned seizing in the 1st reply, which I believe usually has to do with an oil supply problem. Difficult job sorting it out, but to be positive, Simon, maybe look at it this way: it's not a problem, but an opportunity  ;) Lot's of insight will come out of this, and a well running bike.
Title: Re: What goes in this hole then?
Post by: RichardL on 21.08. 2009 08:09
E,

You are correct. I was wrong to refer to white as oil, but I just assumed Simon was using "white" loosely.

Richard L.
Title: Re: What goes in this hole then?
Post by: Rusty nuts on 21.08. 2009 12:00
In my humble opinion that's a partial seizure, no question.
That & or a broken/stuck ring will give you clouds of white smoke.

I had a Triumph way back that I used as a dispatch bike in London weekdays &  thrashed down the A3 to Sussex everyweekend & on several occassions it produced more smoke than the whole Red Arrows team put together!
cleaned up pistons fitted new rings & thrashed again!

If it was mine I would remove piston & check it & barrels for ovality.
If you're not confident about determining this, take piston & barrells to local rebore shop & have them check.
In that first pic it looks as if there may be a small nick out of the bottom of the skirt?
If all OK, i.e not too bad, put it back together.

I would fit new rings regardless, there is too much "blow by" between first & second ring & also between piston crown & first ring.
Hard to tell from photo how deep piston scoring is but looks salvageable.
 Bore should not have suffered so much as harder material.
If it's light, dress with fine grade wet & dry.
You may want to consider giving barrels a light hone to aid new rings bedding in either DIY with wet &dry or get your local rebore shop to do it.

Clean piston crowns, ring grooves
Remember to gap your rings correctly, ensure new ring gaps are not all in line about 120 degrees apart ideally.

Chuck it back together & go for a ride while the weathers still reasonable.
Speaking of which.................

Rusty
The Artful Bodger
Title: Re: What goes in this hole then?
Post by: RichardL on 21.08. 2009 12:38
a broken/stuck ring will give you clouds of white smoke.

...and that top ring is certainly looking like it might be stuck or too stiff in the gap, considering the blowby path. Perhaps the partial siezure has damaged the ring lands and that is keeping the ring(s) from taking to the cylinder walls.

The good news is, you didn't disassemble for nothing.

Richard L.

Title: Re: What goes in this hole then?
Post by: olev on 21.08. 2009 14:33
Cus, A while back I mentioned the local Vincent yahoos used 3 piece oil rings from some sort of mitsubshi in their engines. At the time I was hoping someone in the forum would leap in with a direct replacement for an A7.
While i'm terrified these rings would destroy the unique character of the engine, I'm prepared to take a chance that despite the lack of smoke, misfiring and compression it will still seem like a BSA.
Please tell me about your rings.
cheers
Title: Re: What goes in this hole then?
Post by: beezalex on 21.08. 2009 20:33
If it was mine I would remove piston & check it & barrels for ovality.

I would certainly hope that the piston is oval...
Title: Re: What goes in this hole then?
Post by: Rusty nuts on 21.08. 2009 21:02
If it was mine I would remove piston & check it & barrels for ovality.

I would certainly hope that the piston is oval...

Oops yes, but not the barrel! Distortion is probably a better word. Wriggle wriggle!!!!!!  *respect*
Title: Re: What goes in this hole then?
Post by: cus on 21.08. 2009 23:07
G'day Olev,
I had already purchased new rings, but my mechanic said he wasn't happy to fit the one peice oil ring. He had a contact in Melbourne, Victoria,
that can supply rings for anything, so I called him up, great guy & very informative, sent down my new Hepolite pistons, he has to alter the ring rebate
slightly on the pistons, did a beautiful job. He is called Pacific Engine Parts.

Cus
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 22.08. 2009 00:10
Hi All,
regarding 3 piece oil rings,a source of these is,

Cords Duaflex

Mayphil Industrial Estate, Goatmill Road, Dowlais, Merthyr Tydfil., Mid Glamorgan CF48 3TF

p: 01685 353240  f: 01685 353241

http://www.cordsduaflex.com

Email Cords Duaflex

There are various reports on the benefits of fitting this type of rings to old engines,
satisfy yourselves!!!
I fitted a set to a Commando a long time ago and its still going strong!
Cheers
John O R
Title: Re: What goes in this hole then?
Post by: Mosin on 04.09. 2009 20:17
Hi,

I have just returned home after working away for a couple of weeks and ben met with the site of my poor A7 in pieces standing in the dining room. It seems like the next step is to try and establish the size of the pistons so that I can obtain some new rings. Is there an easy way to do this or is it just down to measuring?

I don't think that there is a rebore shop within about 100 miles of where I am, so it might be a bit of a struggle getting the barrels checked unless I send them off somewhere.

Also, I have heard some talk of "honing" can anyone expand on this for me a little?

Sorry to be a pain, but I really want to crack on with this, partly because it will be nice to have my bike back, but also because I don't want to risk loosing interest in the project and it sitting there indefinately - although I suspect that my wife and the imminent arrival of my second child in the next three weeks would prevent this from happening!
Title: Re: What goes in this hole then?
Post by: a10gf on 04.09. 2009 20:33
Quote
Sorry to be a pain
No pain, such posts + questions with following answers are the reason for the forum's existence !
Title: Re: What goes in this hole then?
Post by: RichardL on 04.09. 2009 21:29
Simon,

Here is a video that I think decently shows DIY cylinder honing (or, if you will, deglazing) http://www.youtube.com/watch?v=82OMO1ArSkk .   Here in the states, the tool that's shown is available at about every retail auto parts store. For laughs, I tried to figure out where you might buy one in Cumbria, but Halfords does not seem to have them, though you might try.

As for the piston size, it should be stamped in the top of the pistons if they are any oversize at all. Nevertheless, you could hardly expect to do this project without owning or having the use of a decent quality dial or digital caliper like the one in the picture for about 30 GBP. For the bore diameter, a cheap set of telescopic gauges could do it, where you use the gauge to fit the I.D. of the cylinder then measure that with your caliper.

The real issue is, does the piston properly fit the bore? This could be checked with feeler gauges at the skirt of the piston 90 degrees from the line of the gudgeon. As a basis, this clearance should be between 0.003" and 0.006", the latter may be a bit loose, but probabaly not a real running problem.

Richard L.

EDIT: Here is a honing description. http://www.realclassic.co.uk/techfiles/tech05010600.html
Title: Re: What goes in this hole then?
Post by: Mosin on 05.09. 2009 11:19
Cheers Richard. I've just cleaned up the top of my pistons and they are clearly stamped 11603 and +020 so I guess that clears that one up. I should be able to get a set of +020 rings easily enough.

I have also just ordered a digital calliper - I've been meaning to get one for ages so a long overdue purchase I think. I'm sure I'll not regret it!

One thing did occur to me though. If my problems stem from some sort of oil supply/circulation issue as most people seem to suspect, would this not have affected both cylinders simultaniously? As can be seen from my photos, the right hand cylinder appears to be pretty much fine.

Oh, and finally (but only for the time being no doubt) is there some sort of a 'knack' to removing and refitting the piston rings? I don't want to risk breaking anything or making matters worse than they are already.

Many thanks as always,


Simon
Title: Re: What goes in this hole then?
Post by: RichardL on 05.09. 2009 13:35
Simon,

First, ring removal and replacement. A tool for this is cheap enough, probably as low as 8 GBP (and up). It can be done by hand, but brand-new broken rings are quite possible. In any case the tool must be used cautiously as well, only spreading the ring just as far as necessary to get over the piston diameter. When you put it back together, you will need two ring compressors, as in

http://cgi.ebay.co.uk/NEW-PISTON-RING-COMPRESSOR-65-70mm-BSA-TRIUMPH-AJSARIEL_W0QQitemZ140333943763QQcmdZViewItemQQptZUK_Motorcycle_Parts?hash=item20ac8e0bd3&_trksid=p3286.c0.m14

Regarding oil, the left side is most likely to starve first for a variety of possibilities: bad pump; low oil supply in tank; clogged flexible lines; clogged oil pickup tube in sump; bad right-side main bearing; bad pressure relief valve; clogged sludge trap (in later models, a tube through the crankshaft that separates heavier particles from oil by centrifugal force); dirt, metal or other large particles in oil; too loose right side rod bearing; clogged pressure equalizing hole in left side piston rod (maybe, controversial herein as to its potential guilt). The first four of these, I think, probably would have resulted in siezing on both sides. [Gents-at-large, please fill in causes I may have missed, after all, much of what I know I owe to you (or, if I were in the South, which I am not, "y'all")].

Before blaming oil completely, I think you should determine, to a certainty, that piston clearance on the two cylinders was the same before the failure and that that clearance was enough, for openers, let's asy 0.003". If just the left was too small, it may not have been an oil issue. If it turns out to be oil, and the chances for that are pretty good, you are in for a much bigger engine rebuiding job. If you don't already have it, get a copy of the Haynes shop manual. There is some not perfect information in there, but, for a beginner with an A7 or A10, I think it is a must. If you want to find references in this forum as to Haynes' inaccuracies, use the search tab, above, and search for "haynes".

I think that must be it from me, for now.

Richard L.
Title: Re: What goes in this hole then?
Post by: a10gf on 05.09. 2009 15:42
Good advices from Richard. Here is another twist, pieces of hard cardboard, plastic or thin metal

If you do not have some books, get them, you'll find tons of small and big tips to get things done the best way and in the right order, + lists of clearances, gaps etc etc, see books (http://www.a7a10.net/forum/index.php?topic=348.0).
Title: Re: What goes in this hole then?
Post by: nigeldtr on 05.09. 2009 21:39
Hello Simon,

Just read this thread and sounds like what I had happen to me, you may have seen the thread "Advice needed engine tightening up". A bit heart breaking when this happens. Have a look at the good comments from the guys on the problems I have encountered and I hope you find the cause.

Regards

Nigel
Title: Re: What goes in this hole then?
Post by: Mosin on 06.09. 2009 16:17
Finally, a glimmer of hope!

I have just (and I should stress, not for the first time) had another look at the sump plate area, as it seemed to me that the engine was pretty much "drowning" in oil, despite the fact that the oil appeared to be returning to the tank last time I had the engine running. I took a length of stiff wire and had a good rummage about in the end of the pipe which drops down through the gauze into the sump plate (The scavenger pipe I think this is). After a good bit of delving about, I finally managed to release a lump of instant gasket which was about 2mm across and 3mm long! It must have been virtually bloking the scavenger pipe altogether. How I missed it the first couple of times, I have absolutely no idea! Anyway, it's out now and I am cautiously optimistic that I may have finally got to the bottom of my woes...

My current hypothesis is:

Oil pump pumping oil into the engine faster than it was being returned to the tank - engine gradually filling with oil - engine overheating - oil finally being blown up past the piston rings, past the valves and out of the hole that I first started with! (or perhaps just out of the rocker cover and cylinder head gaskets).

Does this sound at all like a plausable possibility?

Simon
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 06.09. 2009 17:31
Hi Simon,
"See I told ya" *smile* *smile* *smile*
I feel you should now remove the oilpump and use some aerosol cans of engine cleaner and an airline to clean out ALL the oilways, pipes and oiltank,
The oilway from the sump pipe goes up to the oil pump.
I dont understand how you could have poked a wire up this as there should be a captured ball bearing at the sump end
this acts as a one way valve to keep the return side of the oilpump primed????
Remove the pressure relief valve at the front of the crankcase and this will give you access to the oilways from the pump, and to the main bearing and cam gallery.
Remember there is a ball and spring in the delivery oilway behind the pump, the ball can be lifted using the nozzle extension on the aerosol  cleaner
HTH
Cheers
John O R
Title: Re: What goes in this hole then?
Post by: Mosin on 06.09. 2009 18:26
Cheers John,

The ball bearing in the scavenger pipe is still in situ. I think the problem was that the gasket goo which was forming the obstruction was so soft that my piece of wire was simply going straight through it on my first couple of attempts.

I take on board your suggestions about removing the oil pump and clearing out the oil ways, but I think that before I remove any more bits from my engine I will build up the top end again with new gaskets and piston rings. Starting a whole new job on the oil pump will probably seem much less of an ordeal once the rest of the engine is back together.

Simon
Title: Re: What goes in this hole then?
Post by: A10Boy on 07.09. 2009 12:55
Just my opinion, but since you found a lump of Hermatite like that in an oilway you should remove the timing cover and oil pump as suggested, [its a simple job], and make certain thats its all out BEFORE rebuilding anything otherwise you could be doing work over again.

 *smile*
Title: Re: What goes in this hole then?
Post by: RichardL on 07.09. 2009 14:18
...plus a lot of other work, like: crank grinding; rod-journal replacment; timing-side bearing replacement; etc.  Of course, none of this may happen, but you will be kicking yourself if it does. It would be very easy, here, to say, "take the whole thing apart, check everything, rebuild everything," but, for now, all that is being suggested is look around under the timing cover for other signs of blockage and clean out what is easy.  If, then, you discover more Hermatite (gasket goo) or other issues, you can make a new assessment of the situation.

In my case, I rebuilt my engine with, I think, decent (not expert) engine experience but no experience with an A10 engine. I went merrily along following the Haynes manual but did not know about the importance of a clean sludge trap. I forget right now if you have a sludge trap, but that is not my total point here. The rebuilt engine, after 27 years of not running, started on about the second kick. This was great, until after about 100 miles when I blew a rod bearing, evidently due to crud in the sludge trap. Lesson learned. Re-rebuild now completed with about 1000 miles done.

One more thing I'd like to ask, did you ever determine what your pre-sieze piston clearance was? It's great that you discovered a possible source of blockage but, sometimes, the real problem is hidden by other simultaneous problems.


Richard L.

 
Title: Re: What goes in this hole then?
Post by: Mosin on 07.09. 2009 14:41
Fair enough, you have me convinced. The timing cover & oil pump are coming off tonight when I get home from work! I've got this far, I might as well see the job through.

Richard, I never managed to determine my pre-sieze piston clearance. Is it to late to try and work it out now? I have spent quite a bit of time working on the piston with very fine wet & dry paper and have succeeded in getting most of the sieze marks off it, but I imagine that this will have altered the clearance (although this will only be by a tiny amount). What would be an acceptable tolerance here?

Simon
Title: Re: What goes in this hole then?
Post by: RichardL on 07.09. 2009 15:16
Simon,

I assume you have been following the topic at http://www.a7a10.net/forum/index.php?topic=1194.0 .  There are some similarities between your problems and Nigel's.

As for clearance after the cleanup, I would guess you did not remove much diameter with the wet-dry paper. You could check the difference between pistons with the caliper to judge how much.  If you are now at 0.004"-0.006" clearance, you probabaly started with, at least. 0.003", which would be good, but would also seem to indicate oil shortage rather than simple siezing due to clearances being too tight.

By the way, it's a pleasure trying to help by offering my advice, but I hope others will chime in to confirm and/or offer different or additional advice.

Richard L
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 07.09. 2009 16:34
Hi Simon,
All sound advice,
When the top end is apart you can check the oilway from the camshaft gallery back down to the pressure relief valve (very important)
Cheers
John
Title: Re: What goes in this hole then?
Post by: Mosin on 08.09. 2009 20:41
Good evening Gents,

My wife has gone out for the evening, so I am taking advantage of the situation.

I have removed my timing cover and oil pump as suggested. I was amazed to find a massive amount of grease begind the timing cover which didn't really appear to be doing anything very much (see photo) and also quite a bit of sludge in the bottom of the casing, although this was pretty liquid and didn't seem to be forming any sort of an obstruction. I am now at a bit of a loss as to which of the holes behind the pump I should be cleaning out, looking for ball bearings in, which connects to my scavenger pipe etc. I am attaching a photo of what I am looking at at the minute, so any guidance would be most welcome.

Thanks as always,

Simon
Title: Re: What goes in this hole then?
Post by: rocket man on 08.09. 2009 20:52
hi simon the grease is for the dinamo chain


dave
Title: Re: What goes in this hole then?
Post by: a101960 on 08.09. 2009 21:33
As Rocket Man says, the grease is to lubricate the dynamo drive chain. I am a little concerned to see evidence of red hermatite. If I was you I would clean that all off and just grease the gasket before fitting it. Grease will hold the gasket in place and you will get a leak free seal. I have refitted  my timing cover  three times now with the same gasket using grease and it is oil tight.
Title: Re: What goes in this hole then?
Post by: RichardL on 08.09. 2009 21:40
That's a very good concern, since a chunk of it was found in the oil pickup tube.
Title: Re: What goes in this hole then?
Post by: nigeldtr on 09.09. 2009 13:40
Simon,

Just a couple of things, I found a supplier of a sort of "liquid" grease for the dynamo chain which basically runs down when the engine is stopped and partially solidifies around the chain and lower sprocket when the engine cools. Don't need much of it as it always flows back down. Not sure if you can get something like this in the UK? Second is hows the main bearing? Nice and easy to check with the pump out of the way! Fully agree with not using sealant but grease on the gaskets and faces - saves gaskets and makes getting things apart nice and easy.

Nigel
Title: Re: What goes in this hole then?
Post by: A10Boy on 09.09. 2009 14:03
Well at least the pump gasket area isnt covered in hermatite.

I would check to see where that red shite has been used, remove and clean whatever has been fitted using it, replace whatever without it using new gaskets, clean all oilways and pipes and remove and clean out the oil tank, remove the sump plate and clean that too.

While you have the covers off check for excessive end float on the crank and wear in the timing side bush, if it has wear you might need to consider stripping the bottom end and rebuilding it properly.

When you refit the timing cover, put a good dollop of Low Melting point grease in the dynamo chaincase area and it will melt and lube the chain. That grease in your pic is obviously high melting point as it still in a lump as when it was put in there.
Title: Re: What goes in this hole then?
Post by: A10Boy on 09.09. 2009 14:06
Sorry Nigel, Didnt mean to crash your post.
Title: Re: What goes in this hole then?
Post by: Mosin on 09.09. 2009 16:10
All good advice guys. I am following each suggestion as it comes. The red shite is virtually all gone now and things are beginning to look much cleaner.

As an interesting aside.... I have just removed, checked and replaced the oil feed and return hoses (they were fine) but as I was doing so, the chap in these pictures dropped out of somewhere and fell onto the floor. I have never seen 'im before and I've no idea where he came from. As you can see, he is a little over an inch long and threaded at one end. The threaded end has what looks like a phillips recess in the end of it and the non-threaded end is slightly chamfered.

I know this isn't a great description, but I am not an engineer. I hope that the photos will make up for my poor description. But I am not a photographer either....

Still, at least the sun is shining.


Simon
Title: Re: What goes in this hole then?
Post by: fido on 09.09. 2009 17:35
That looks like it might be a  clutch pushrod adjuster screw but I don't think it is an A10 one. I wonder if it could have rolled off a bench and landed on your bike at some point in the past?
Title: Re: What goes in this hole then?
Post by: bsa-bill on 09.09. 2009 17:41
looks a bit like one of the pins the pump gears spin on, but not exactly as far my memory serves.
Surely no way it could have got from the pump into the oil pipes on its ownsome though.
Looks a bit more like one of the studs that hold the pump on, perhaps snapped off by PO but why stuff it up one of the pipes??
It would certainly do every bit as good a job of oil restriction as red Hermatite.

More mystery

All the best - Bill
Title: Re: What goes in this hole then?
Post by: Mosin on 09.09. 2009 18:36
Just to clarify - it wasn't actually stuffed into the pipe. That is just the job I was doing when I disturbed it. I also have the timing cover off, so it's possible that it has come from somewhere inside there and I just disturbed it with my hand/the spanner as I was tightening the hose back onto the back of the oil tank.

I don't think that it is a cluth push rod adjuster - the diameter is way to narrow for that. It's only a couple of mm accross at most.


Simon
Title: Re: What goes in this hole then?
Post by: nigeldtr on 09.09. 2009 20:14
simon, l think you have started a quiz with what looks like a long lost Dingsbums (lovely German word for a thingamabob) *smile*

Andy - no problems.

Nigel
Title: Re: What goes in this hole then?
Post by: beezalex on 09.09. 2009 20:29
Generator strap pin.
Title: Re: What goes in this hole then?
Post by: Mosin on 09.09. 2009 20:46
Generator strap pin.

Good guess Alex, but my Generator strap pin is still in place. And also this pin I have found is only just over an inch long. In fact, its dimensions are 25mm x 4mm. The generator strap pin is much longer than this.

I am currently thinking that it must be designed to screw into something from one end (using the phillips slot at the threaded end). The fact that the other end has a slight chamfer would seem to back this up and to my mind it looks like some sort of an adjuster to regulate the flow of something (liquid/oil/air?) passing through whatever it is designed to be screwed into. I took the carb off weeks ago and it is nowhere near the bike, so it can't be that. I suppose it could also be an adjuster to regulate the movement of some other moving part (a lever or something)? I am at a loss.

The one thing that I DO know is that I am reluctant to continue reassembling the engine until I have positively identified this part. I'd hate to get it all back together only to have to strip it down again when I find out what it is.
Title: Re: What goes in this hole then?
Post by: fido on 09.09. 2009 22:02
I think if it was a BSA part one of us would have recognised it.
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 09.09. 2009 22:43
Hi Simon,
I dont believe its from your BSA,
As far as I know there are no phillips/pozi screws on A7/10's
Can you identify the thread?
Cheers
John O R
PS did you poke something through the oil pipes? I just had a thought did some PO push one of those hidden anti syphon valves up the oil pipes?????
Title: Re: What goes in this hole then?
Post by: a10gf on 09.09. 2009 23:50
nigeldtr wrote
'long lost Dingsbums'
My grandmother used that expression for any small thing she could not immediately identify.
 *smile* +  lol

sorry for the offtopic
Title: Re: What goes in this hole then?
Post by: Mosin on 10.09. 2009 12:07
*clears throat and looks at feet bashfully before typing*


Well chaps, the good news is that I now know what the mystery pin is. The bad news is that I appear to have wasted everyones time for the past 24 hours.

This morning I picked up my trusty adjustable spanner to do a job on a different bike (yes, the same spanner that I had been using yesterday when I dislodged the mystery pin). I immediately noticed that the adjuster worm on the spanner was very loose. Almost as if the pin which was supposed to go through it and fix it to the main body of the spanner was missing..... Sure enough, I screwed my mystery pin into it and needless to say it fitted perfectly.

I will now shuffle off into a corner somewhere and stop wasting people's time. By all means, please feel free to rip the *** out of me mercilessly for the rest of the day.


*red* *red* *red* *red* *red* *red* *red* *red*

Simon
Title: Re: What goes in this hole then?
Post by: RichardL on 10.09. 2009 12:52
First, I knew that thing looked familiar.

Second, it was a good excuse to review the blow-up drawings.


Third, no need for extensive embarrassment, though, I suppose some is unavoidable. It is far from the only and, I think, far from the craziest goof someone here has made.

Fourth, hey, at least your wrench is working.

Regards,

Richard L.
Title: Re: What goes in this hole then?
Post by: A10Boy on 10.09. 2009 13:26
Simon, I think you deserve some embarrassment for that so here's a question;

You mean to say that you were actually using a frikkin ADJUSTABLE SPANNER, what?s more a poorly maintained ADJUSTABLE frikkin SPANNER on your beloved BSA ??

Tut Tut....

 ;)
Title: Re: What goes in this hole then?
Post by: bsa-bill on 10.09. 2009 16:19
Join the club mate

To be honest I'm pleased it not just me

All the best - Bill
Title: Re: What goes in this hole then?
Post by: Mosin on 11.09. 2009 21:36
OK, This evening I have refitted my lovely clean rebuilt oil pump together with the timing cover and its new gasket.

Filled with enthusiasm, I then embarked on putting the barrell back on. Three hours later I have still not managed it, despite having borrowed a set of piston ring clamps. I just don't seem to be able to get the barrells to slide evenly down over the pistons. I either get them going down unevenly and sticking, or else I end up with the clamps too slack and them just dropping down and releasing the rings before I have managed to get the barrells over them.

I have now given up for the evening before I end up breaking something.

Are there any tricks or tips that anyone can offer me on how to go about doing this job?

Simon
Title: Re: What goes in this hole then?
Post by: rocket man on 11.09. 2009 22:48
h iSimon i tried  a good trick i tied the barrels to the frame and pushed the pistons
up into the barrels very slowly pushing each ring into them one at a time you might
need someone to help you as its very tricky or you could use your ring clamps
which will make it easer



dave
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 11.09. 2009 22:53
Hi Simon,
It can be a tricky job on your own!!!
You can use some parallel pieces of metal to support the pistons as you lower the cylinder
another pair of hands is also advisable if you have not done this before
Lube up the ringclamps well  and tighten until the clamp is just free to turn on the piston
the parallels will keep the pistons upright, place the cylinder over them and gently push the cylinder down squarely!
HTH
John O R
Title: Re: What goes in this hole then?
Post by: Richard on 11.09. 2009 23:08
John has pipped me by replying first but I use two strips but plastic bits that were cut from my  facia board when fitting it, across the crancase each side of the rods then bring the pistons down onto them, this keeps the pistons secure and then I positon the ring gaps and oil the piston and rings then place the barrels gently on top and using a plastic stylis from a pda i carefully push the rings in one at a time on each piston while keeping a gentle pressure on the barrals with my other hand it is a bit hairy at first but i have done this for some time now also with my A65 I find it easier than using ring clamps as I just cannot get on with them, but it stops me getting frustrated when the clamp goes down and the ring pops back out
It may well be that if I was shown the technique of using clamps by someone who knew the knack then it may work for me but until then the above method works
Richard
Warning 
there is a greater chance of breaking a ring with my method
Title: Re: What goes in this hole then?
Post by: nigeldtr on 12.09. 2009 20:19
Hi Simon,

Not being funny but what sort of ring clamps are you using. I originally had some that we like a long pieces of spring steel coiled up and adjusted with a key. I found these were  either too loose or too tight (un-even pressure not closing clyindrically) and decided to buy ones of a single ring with a screw for tightening. These worked fine, nipped up and then just eased off. My son lowered the barrels while I checked the rod cutouts at the bottom of the barrels to see the rings were going in ok. With two, went togther relatively easy (the nearest thing to giving birth that a man will experience). I used to do this all by hand but after breaking a number of rings, I prefer to use the one piece clamps. If I get time I will add a pictures tomorow.

PS I used a couple of 5 " gauge plastic railway sleepers to support the pistons - I think in the instruction booklet they recomend 2 peices of 3/4" wood and cloth stuffed in around the crankcase opening to stop any bits falling down the hole *smiley4*

Nigel
Title: Re: What goes in this hole then?
Post by: trevinoz on 12.09. 2009 22:17
Nigel,
         I have a set of Terrys ring compressors which I bought over 40 years ago. They were available in several sizes and were cheap.
They are just  bands of mild steel with a rolled end which captivates a toggle and screw and the other end is like a hook which accepts a threaded toggle.
Very easy to use. I use a pair of socket extension drives to support the pistons when fitting the barrel.
Trev.
Title: Re: What goes in this hole then?
Post by: Mosin on 12.09. 2009 22:32
Well I've now spent a total of five hours trying unsuccessfully to get the bloody barrell down over the pistons, using every single one of the hints and tips suggested here. Finally, I realised the problem....

I had ordered a full set of plus 020 rings from C&D autos. They arrived in two packets both clearly marked plus 020. Just to be on the safe side, I opened the first packet and checked the rings inside the barrells to make sure that the fit was right. It was. Perhaps foolishly, I did not check the second set, assuming that it would be exactly the same as the first. It wasn't. It turns out that C&D sent me one set of plus 20 and one set of plus 60! There was no way on earth that the were ever going to fit into my plus 020 pistons.

As you can imagine I am pretty furious about this and will be on the phone to C&D first thing on Monday morning.

Bah.
Title: Re: What goes in this hole then?
Post by: Richard on 12.09. 2009 22:37
Frustrating
Richard
Title: Re: What goes in this hole then?
Post by: RichardL on 12.09. 2009 23:26
IMHO, you must check and, if necessary, file-fit ring gap for each ring in its target cylinder, even if they are, indeed, both the correct oversize. I assume the judgement of 0.060"-over is based on more than just the end gap not fitting. But that is not my point. When you are sure you have the correct rings you will still need to check all the gaps.

Richard L.
Title: Re: What goes in this hole then?
Post by: orabanda on 13.09. 2009 02:15
I use a similar method to Trev.

(http://i302.photobucket.com/albums/nn82/orabanda/54A10Pistonsfitted.jpg)

These ring clamps came from British Only  (in NZ) and they are low cost but good quality.

A couple of pieces of 1" square soft wood to go under the pistons, and fitting the barrel is a 10 minute job, for one person.

Richard
Title: Re: What goes in this hole then?
Post by: RichardL on 13.09. 2009 06:38
Richard,

Though it's an old picture, it's never too late to say, "beautiful work." Of course, you've spoiled us and we naturally expect no less from you. It's also, I think, a rare shot of a breather pipe in place.

I do wonder, why do you run the blocks longitudinally rather than across the case so that both pistons sit on both blocks, as shown in various manuals?

Richard L.
Title: Re: What goes in this hole then?
Post by: orabanda on 13.09. 2009 07:09
Richard L,
Thanks for the kind comments!
I have never found a breather pipe on the swing arm engines (only the semi-unit), so I made that one.

Here's a better pic:

(http://i302.photobucket.com/albums/nn82/orabanda/54A10enginebreather.jpg)

I simply find it easier to get the 1" wood out afterwards (don't forget to have the base gasket in place!).
More pics from this rebuild:

(http://i302.photobucket.com/albums/nn82/orabanda/54A10frame2.jpg)

(http://i302.photobucket.com/albums/nn82/orabanda/54A10frame3.jpg)
Also, here is this bike on the dyno 2 days ago; more about the timing settings, etc in a post to follow:

(http://i302.photobucket.com/albums/nn82/orabanda/P1010169_resize.jpg)

(http://i302.photobucket.com/albums/nn82/orabanda/54A10resizegraph.jpg)

Regards,
Richard
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 13.09. 2009 14:20
Hi Richard,
Great photos!
Looking through them one shows the battery tray bracket over the frame cross tube, there seems to be a large gap there like on a RGS frame, I have heard that some early (54/55) frames also have the larger gap,
Just curious????
In the photo of the bike on the dyno, it looks like you have a different clutch from standard????
hard to se as its spinning but it looks alloy???
I also thought about fitting a breather pipe but I didnt want to reduce the size if the breather hole, so I left it alone
Cheers
John
Title: Re: What goes in this hole then?
Post by: orabanda on 13.09. 2009 14:43

John,
This is a Suzuki GS550 clutch, which a mate of mine in Perth knocks up.

(http://i302.photobucket.com/albums/nn82/orabanda/54A10clutch2.jpg)
(http://i302.photobucket.com/albums/nn82/orabanda/54A10ColinTieclutch3.jpg)
(http://i302.photobucket.com/albums/nn82/orabanda/P1010172_resize.jpg)

I have them in all of my swing arm bikes.

The rigid and plunger A10 have the standard 6 spring clutch (with the dome cover). Apart from fitting an alloy pressure plate, and setting them up with a dial indicator, they are standard (and really nice clutches).

Here is the standard clutch on my plunger bike:

(http://i302.photobucket.com/albums/nn82/orabanda/IMG_4383.jpg)

Now, I am building a Super Rocket special (BTH maggie, TLS brake, roller bearing timing side bearing, etc...) and have had my mate do a belt drive. I love japanese 2 stroke dirt bikes, and had a spare clutch from a PE400 Suzuki which I am restoring, and this has been converted to belt drive for the Super Rocket.
(http://i302.photobucket.com/albums/nn82/orabanda/A10beltdrive2PE400.jpg)

This is Colin Tie, who prepares the clutches, and one of his many Gokld Stars.

Richard

(http://i302.photobucket.com/albums/nn82/orabanda/ColinTie1resize.jpg)
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 13.09. 2009 18:06
Hi Richard,
 Thanks for all the info, I thought it was something like that,
Does he attach the Suzuki clutch basket to the BSA chain wheel?
and does he modify the clutch centre to fit the BSA/Triumph centre adaptor?
What kind of centre bearing does he use?
Do you have some photos of one dismantled?
I have bought a couple of GSXR clutches on ebay with a view to doing this mod
These are similar to the GS or GSX except they have sawtooth like splines on the outer of the plates,
A friend of mine has a standard one of these clutches on a big bore GSXR 13**cc using a 750, 6 speed box
and it has not given him any trouble!!!!
so I dont think 20something bhp on your flash will bother it!!
However on my SR with high comp pistons and spitfire cam etc, the 4 spring clutch I have presently slips when the engine comes on the cam around 4000rpm,
Hence the Suzuki  conversion!!!!!
Regards
John O R
Title: Re: What goes in this hole then?
Post by: rocket man on 13.09. 2009 21:39
thanks for the pics Richard, you have a very good setup there
and looking at your bikes you do a good job on them lovely



dave
Title: Re: What goes in this hole then?
Post by: orabanda on 13.09. 2009 23:53
John,
Here is more detail on Colin's clutches.
His passion is Gold Stars (here are a couple of them; there's more than this!):

(http://i302.photobucket.com/albums/nn82/orabanda/ColinTieGStarsonfloorresize.jpg)

He rides his bikes every weekend in club events

He is a skilled machinist, and wanted a better clutch for his own bikes.

He buys industrial chain wheels, and adapts the clutch to them. This one is steel sprocket.

 (http://i302.photobucket.com/albums/nn82/orabanda/ColinTieclutchrear.jpg)

(http://i302.photobucket.com/albums/nn82/orabanda/ColinTieclutchside.jpg)

(http://i302.photobucket.com/albums/nn82/orabanda/ColinTieclutch1.jpg)

This is the clutch on my RGS replica. It has an anodised (hardened) alloy sprocket, and is much liter than thges steel.

(http://i302.photobucket.com/albums/nn82/orabanda/RGSClutch2-1.jpg)

I gave him a clutch out of a GN250 Suzuki which he adapted into his 350 Gold Star; he said it was a great clutch!

Regards,

Richard
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 14.09. 2009 21:13
Hi Richard,
Many thanks for the great photos and info,
I looked and photographed a secondhand "Pearson" clutch at the Founders Day Show and autojumble in the UK this year,
He makes the chain wheel and basket as one piece, however it must have been running well out of line as there was a fair amount of wear on the sprocket!!! At £270 I felt I could do better!
There also seemed to be some fretting between the steel centre adaptor and the alloy clutch inner
I paid £40 for a complete Suzuki clutch and £30 for almost a complete other including a second Basket

Do you know the bearing number for the centre bearing on your clutches?

Attached are some photos of the Pearson clutch for comparison, this one has a modified centre As Mr Pearson sells a seal kit for the sliding plate.
It will be a couple of months before I get to this project as I am building another garage, I cant even walk around the bikes at the minute *eek* *eek* *eek*
I am taking early retirement before the year end, this should allow lots more time to play in the workshop
*smile* *smile*.

Regards
John O R
Title: Re: What goes in this hole then?
Post by: Mosin on 17.09. 2009 20:09
Well, I was beginning to think that the day would never come....

But yesterday my new piston rings arrived (the correct size this time) and the barrells slid on just fine using the clamps. My rebuilt Cylinder Head went on next no problem followed by rocker box, exhausts, carb, sump plate and tank. This morning I put some fresh oil in her kicked her over and she fired! Initially there was quite a bit of white smoke coming from the left pipe (same one as before) and my heart sank. But after a couple of minutes, this dissapeared and the engine settled down to a nice tick over with the oil pumping through at a very healthy rate. I went for  couple of short runs and noticed that the engine seemed to be running quite hot and is reluctant to start again from hot, even though it starts from cold just fine. Aside from this, I have now covered about 12 miles and everything else seems to be ok. Tonight I have removed the sump plug and all that drained out was the egg-cup or so of oil that you would expect. A good result.

Thanks again for the help, support and encouragement guys. Without this forum I would have given up long ago.

Simon
Title: Re: What goes in this hole then?
Post by: nigeldtr on 17.09. 2009 21:37
Hi simon,

Great news - have you checked th eignition timing?

Nigel
Title: Re: What goes in this hole then?
Post by: Mosin on 17.09. 2009 22:00
Hi simon,

Great news - have you checked th eignition timing?

Nigel

I haven't, but I have never touched the timing throughout all of this. Is it likely to need resetting?
Title: Re: What goes in this hole then?
Post by: A10Boy on 18.09. 2009 13:10
Simon
Well done. I love it when a plan comes together.  *smile*

One thing, you might find that the engine needs slightly different carb settings after a rebuild
Title: Re: What goes in this hole then?
Post by: nigeldtr on 18.09. 2009 18:36
Simon,
I only mentioned the ignition timing as I had a similar failure on my A10 and when it failed it was very hot. When I put things back together, I decided to check the timing and found it to be advanced, which if I am correct, gives much higher combustion temperatures.

Nigel

Title: Re: What goes in this hole then?
Post by: Mosin on 18.09. 2009 19:34
I've had a tinker with the carb and re-re-set the valve clearences. It's running much better now! Still a bit harder to start from warm, but not too bad. I've done twenty five miles on it this afternoon with a grin on my face for every single one of them!
Title: Re: What goes in this hole then?
Post by: rocket man on 18.09. 2009 22:59
well done mate  *smile*
Title: Re: What goes in this hole then?
Post by: Mosin on 19.09. 2009 20:48
I am sure that opinions will differ widely on this subject, but I wonder what people would suggest as being a suitable "running-in" period for my newly rebuilt engine? I have now covered about 100 miles on it, very carefully, and it is still running beautifully with no smoke or overheating and just a nice stady purr...
Title: Re: What goes in this hole then?
Post by: rocket man on 19.09. 2009 21:31
id say run her in for another 500 miles say half throttle
then slowly increase your speed after that you have to be
gentle with an old bike im still running mine in ive done about
300 miles now i ride at 55 miles an hour which i think is a good
speed for her when i reach 600 miles i will be riding her at about 65
which is the fastest i will be going on the old girl
Title: Re: What goes in this hole then?
Post by: Rocket Racer on 19.04. 2010 07:25
Can you tell me any more about the source of these sprockets? I enquired with my usual blank sprocket supplier and they couldnt do a 428 43T sprocket, nothing smaller than 46 Teeth...
The picture shows what looks a fair bit wider than a single sprocket.





He buys industrial chain wheels, and adapts the clutch to them. This one is steel sprocket.

 
Title: Re: What goes in this hole then?
Post by: chaterlea25 on 19.04. 2010 22:54
Hi Rocket Racer,
I have bought some correct sized 43tooth blank sprockets  from Sprockets unlimited in the UK,

www.sprocketsunlimited.com/

they have them in steel or Dural, 16 and18 £. +vat

HTH
John O R
Title: Re: What goes in this hole then?
Post by: Rocket Racer on 06.05. 2010 04:26
Thanks for that, I have been in touch with them and have one ordered. Then just need to sort out a bearing and a centre...
Title: Re: What goes in this hole then?
Post by: BSA_54A10 on 08.05. 2010 01:30
You can do the same thing with a Yamaha SR , XT , XS clutch.
These are all rivited to the driven gear behind them so they can be drilled out and bolted inside the existing BSA clutch drum.
The center of the Yamaha clutch is bigger than the BSA one so it can be machined out to fit over the BSA one.
I am sure that there are a lot of other ones that could be made to fit in a similar mannar.

OTOH it is a lot simpler to buy an off the shelf Triumph conversion to take the Triumph ( and latter BSA ) 3 spring clutch, fit an alloy pressure plate and top hat radial roller lifter
Title: Re: What goes in this hole then?
Post by: Big Nick on 18.05. 2010 19:12
looks like a home made breather to me as well. i also have adapted the rear inspection cover to add breather pipe
Title: Re: What goes in this hole then?
Post by: db133 on 23.12. 2010 10:27
Hi

Sorry to butt in etc.

Ref:I have them in all of my swing arm bikes.

Quote
The rigid and plunger A10 have the standard 6 spring clutch (with the dome cover). Apart from fitting an alloy pressure plate, and setting them up with a dial indicator, they are standard (and really nice clutches).
I do not understand how a clutch is set up with a dial indicator.
Will you be kind and explain how its done ?

Kind regards
Title: Re: What goes in this hole then?
Post by: bsa-bill on 23.12. 2010 11:27
You need to adjust the springs so that A. you can operate the clutch with one hand  *smiley4* and B so that the pressure plate lifts square so in turn the plates will all part evenly, this is where a dial gauge can be a great help set up to just touch the pressure plate ( avoiding the spring bits obviously ) it will show how even you have adjusted the springs
Title: Re: What goes in this hole then?
Post by: BSA_54A10 on 23.12. 2010 12:41
Yep that is how you do it.
Set the dial to about 1/2 scale with the clutch pulled in against the pressure plate adjacent to a spring
rotate the clutch 1/6 of a turn, pull the lever and write down the readings.
Ditto for the other 4 studs.
Tighten the high ones loosen the low ones
Repeat the measurements
Repeat the adjustments
When you think you have got it pat. pull in the clutch and kick the bike over  few times them measure again.
Eventually you should be able to get it dead square, but you are liable to die of old age first.
However when done properly it is a joy to use.
It is just a pia to adjust properly.
Title: Re: What goes in this hole then?
Post by: dpaddock on 29.12. 2010 20:09
Just got around to viewing this posting and I am astounded to see the rocker box with the threaded hole; I have its relative in my A10 spares box!
I got the thing from a friend several years ago who was purging his garage. I have no idea of its history but I have to say it's not a bodge. As mentioned by Trev, is the Ariel Huntmaster box the same as the BSA Twin?

And so continues the saga. . .

David
Title: Re: What goes in this hole then?
Post by: BSA_54A10 on 30.12. 2010 11:21
Rocker box yes
Gearbox & clutch no
Title: Re: What goes in this hole then?
Post by: trevinoz on 30.12. 2010 20:55
Sorry Trevor,
                       The Huntmaster rocker box casting is not the same as the BSA type.
The internals are, though.All externals of the Ariel engine are unique to that machine but the internals are all A10.
Trev.