The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => A7 & A10 Engine => Topic started by: a10sausage on 10.02. 2009 17:06

Title: covers our street in a haze of blue smoke
Post by: a10sausage on 10.02. 2009 17:06
hi...if i have not run my 1960 flash for a couple of weeks i get a huge thick blue smoke trail out of the right hand exhaust (blots out my street) for the first 150 yards then its fine goes like a rocket...this has happend on my last two outings....is ther any body out there with any idea what this could be....cheers!...this is the offending machine http://www.youtube.com/watch?v=L7TYqwwqDC0 (http://www.youtube.com/watch?v=L7TYqwwqDC0) *sad2* *eek*
Title: Re: smoke trail like concorde
Post by: zitman on 10.02. 2009 17:26
Hi,

Sounds to me like its wet sumped.  And after a short distance the scavenge side of the pump has cleared the excess oil from the sump.  My Dommie used to do the same if left for a couple of weeks.

Z
Title: Re: smoke trail like concorde
Post by: A10Boy on 10.02. 2009 18:00
I agree with Z

To test the theory, next time you have left it a while and go to start it, first remove the "sump" drain plug. If you get any quantity of out, put the drain plug back in, top up the oil tank and start her up.

If it is wet sumping, you can buy a one way valve which fits on the supply oil line for about 35 of those hard earned quids.
Title: Re: smoke trail like concorde
Post by: bsa-bill on 10.02. 2009 19:31
Hi - mine does the same thing but usualy the left side and an odd occasion the right side.
Not wet sumping IMO, probably oil leaking past the valve guides drains down (inlet onto piston crown - exhaust down into the exhaust pipe where it soaks into the carbon) depending how the engine stops will determine which side smokes.
Oil that gets into the exhaust pipe will soak into the carbon and take a while to clear, oil onto the piston will probably burn off more or less straight away.
Wet sumping would leave a little puddle underneath the engine or a large one if left long enough, some oil will always be left in the sump but the scavenging side of the pump should clear this fairly quickly if not then it would be blown out of the breather tube onto your garage floor.

Well thats my theory, your welcome to agree or disprove it, any comment welcome *computer*
All the best - Bill
Title: Re: smoke trail like concorde
Post by: a10sausage on 10.02. 2009 19:41
wow...very fast answers...and two solutions....as long as it does not do any damage....thanks to you all....any more ideas welcome
Title: Re: smoke trail like concorde
Post by: A10Boy on 10.02. 2009 19:54
Bill

Yes you are probably right about valve guide leaks, but as usual, the best way to find out is to rule out the easy to find items first. If after draining it still smokes its probably guides as you say.

Not all cases of wet sumping leave oil on the floor [or do they?], wouldn't it be difficult to tell the difference between that and the other general oil leaks anyway ?

Mr Z is talking about a Casey Jones type of smoke cloud, that seems a lot of smoke from just a few drops of oil down an exhaust pipe - or is it ??

Title: Re: smoke trail like concorde
Post by: bsa-bill on 10.02. 2009 21:46
Hi A10boy
have to agree that my theory is suspect around the point you make about the small amount of oil  that might leak down a giude once an engine has stopped.
however my engine has had a rebore and new pistons and rings but still smokes ( yes spectacularly at times when first started) so if the rings have bed in as they should have you would not expect any oil in the sump to be burnt at a rate to make that much smoke, also if wet sumping was the cause you would expect smoke from both barrels .

Then again if you've ever read the "smoke theory" you will know it's probably an electrical fault *smile*

All the best - Bill
Title: Re: smoke trail like concorde
Post by: fido on 11.02. 2009 06:20
....any more ideas welcome

Yes, try to keep your speed below Mach 1  *lol*
Title: Re: covers our street in a haze of blue smoke
Post by: a10sausage on 11.02. 2009 18:36
 *smile*mach 1..is that all....mmm i am not trying hard enough....there must be more horse power in this old a10 engine somewhere...i am thinking of buying some new rear silencers soon are armours pipes good..if so does any body use them.
Title: Re: covers our street in a haze of blue smoke
Post by: TJ on 11.02. 2009 19:18
Hi A10 Sausage,
I bought a pipe and silencer for a Starfire I'm rebuilding from Armours, I wasn't impressed at all. No way will I buy from them again !!! *sad2* *sad2*

TJ
Title: Re: covers our street in a haze of blue smoke
Post by: bsa-bill on 11.02. 2009 20:43
Campbells silencers are still available but I really dont know from where, I bought a new pair from someone on Ebay ( can't remember who but know he is known in BSA circles) maybe he's on the forum

All the best - Bill
Title: Re: covers our street in a haze of blue smoke
Post by: LJ. on 11.02. 2009 22:59
Yes I'll certainly reccommend a pair of Campbell silencers. Luckily I bought my A10 with them already fitted and I'll say they sound better than the Goldie silencers on my other A10. Also I have the campbells on the Star Twin too, again I was lucky that they were also fitted to that bike as well.

I knew they were South East London somewhere and a quick search reveals a web address.

http://www.campbellcustom.co.uk/

Another good silencers and they were the Burgess ones, sounds very similar to Campbells but I dont know if they are still around, I suspect not.
Title: Re: covers our street in a haze of blue smoke
Post by: a10sausage on 11.02. 2009 23:15
hi to all....i have just had a lppk on the campbells website...i cant see any pipes for bsa or old brit bikes....can anybody else help with a good recommend for silencers..burgess  are not on sale anymore...cheers.
Title: Re: covers our street in a haze of blue smoke
Post by: dpaddock on 12.02. 2009 02:30
I tend to go with the valve guide theory. Not just excessive clearance between valve stem and guide bore but also a loose guide, especially in the alloy head.
     David
Title: Re: covers our street in a haze of blue smoke
Post by: Chrisf1 on 12.02. 2009 10:16
I bought a pair of swept back pipes and goldie silencers from armours the goldies were OK nothing special for the money but the pipes would not go anywhere near after trailering the bike and exhausts there (150 miles each way) they agreed they do not fit they made various cuts and bends and 3 weeks later i received my new set which still did not fit i got my money back eventually and bought a set from bantam john at kempton straight on no problem see pic
Title: Re: covers our street in a haze of blue smoke
Post by: A10Boy on 12.02. 2009 10:44
Maybe it is a loose guide, but don't they get looser as the head warms up and make a rattling noise?

Doesn't blue smoke indicate combusted oil, I would have thought that oil in an exhaust would have heated and vaporised progressively as the exhaust warms up rather than combusted. Blue smoke indicates to me that the problem is going on inside the engine.

For my two-penn'oth, if it was my bike there are three things I would do, [sorry if you've already thought of this].

1/ Remove the sump plug just to see its it wet sumping, and if its not, put the plug back in and go to item 2.

2/ Remove the offending exhaust pipe [before starting the engine] to see if there is oil in there, and if not leave the pipe off and remove the plugs, turn the engine over till the exhaust valve opens and look in there with a lamp, you should see from the coke / witness marks around the bottom of the valve guide if its loose. If there are no witness marks on the Guide its probably tight, but if the valve stem is oily then its a worn guide. [you wont see what happening to the inlet valve and guide using this method but it at least shows what is going on with the exhaust valve and guide]

3/ If there is no obvious wet oil on the piston or valve or guide or coming from the exhaust port, put the plugs back in, leave the exhaust off, put some ear defenders on and start her up. You should then see if wet oil is being blown out of the exhaust immediately following start up or what's going on.

If there is no wet sumping, and the piston is oily, but the Ex valve is dry, and the Ex guide is tight, you will need to remove the rocker box to check the inlet valve guide tightness as it would indicate a possible problem here.

One question, does it make any difference whether you park it on the centre or side stands ??

Sorry that turned into a long one once I started....



Title: Re: covers our street in a haze of blue smoke
Post by: a10sausage on 12.02. 2009 18:58
i will remove the sump plug over the weekend...stuck with the dreaded decorating at the moment....bantam john looks like it might be worth a browse for silencers as i am going to the stafford show in april
Title: Re: covers our street in a haze of blue smoke
Post by: olev on 13.02. 2009 12:11
When you drop the sump off, check there is not a bit of poop caught under the ball in the oil pickup.

otherwise,
A postage discount will apply if you buy all 3 springs, cheers

www.a7a10.net/forum/index.php?topic=848.0



Title: Re: covers our street in a haze of blue smoke
Post by: a10sausage on 13.02. 2009 12:56
ok....here we go...just undone the sump drain plug and 3/4 of a pint of oil drained out....aaaarrrggghhhh! would this be classed as wet sumping....next move anybody...or info on ANTI WET SUMP VALVE  does This valve fit in the  oil supply line and stops the engine filling with oil while bike is sitting for extended periods
Title: Re: covers our street in a haze of blue smoke
Post by: LJ. on 13.02. 2009 13:58
Try using a thicker oil first... I use straight 50 and never have problems with wet sumping. A cupful of oil in the sump is about normal.
Title: Re: covers our street in a haze of blue smoke
Post by: a10sausage on 13.02. 2009 14:06
just run the bike round the street after draining the sump...no smoke at all.
Title: Re: covers our street in a haze of blue smoke
Post by: A10Boy on 13.02. 2009 16:39
I am glad you found the problem.

You probably need one of these, there are two types, one fits into the crankcase, the other goes in the oil line.

http://cgi.ebay.co.uk/BSA-NORTON-TRIUMPH-ANTI-WET-SUMPING-VALVE-COMPLETE_W0QQitemZ400030120495QQihZ027QQcategoryZ108839QQssPageNameZWDVWQQrdZ1QQcmdZViewItem (http://cgi.ebay.co.uk/BSA-NORTON-TRIUMPH-ANTI-WET-SUMPING-VALVE-COMPLETE_W0QQitemZ400030120495QQihZ027QQcategoryZ108839QQssPageNameZWDVWQQrdZ1QQcmdZViewItem)

If you dont want to do ebay their phone number is 01558 668579

Cheers
Title: Re: covers our street in a haze of blue smoke
Post by: TJ on 13.02. 2009 18:08
Hi everyone,... re ARMOURS.
The system I bought for my Starfire build ( see 8 above ) came via mail order, as I wasn't ready to fit them straight away the package was unopened for a couple of months.  When the day came to fit them boy what a dissapointment, .... the high level pipe had a dent on the top run ( very visable area ).  The shorty silencer mounting bracket looked as though it had been shaped by someones dentures ( false teeth ) it was really rough. 
The best laugh was when I offered them to the bike,  the pipe was 9 inches too long !!!  I can here you all saying just cut a bit off.  I did,   like you would.
OK so now its the right length, offer it up again, not looking too bad, maybe I can live with the dent afterall.
On with the silencer,.... should it realy stick out at 45 degree's like it was doing.  I think not, ... the final bend on the pipe was totally wrong.!!!!
Dumped it back into the box and placed it really gently,.... no really gently, honest !!! as far under the bench it would go. 

TJ
Title: Re: covers our street in a haze of blue smoke
Post by: a10sausage on 13.02. 2009 18:57
that anti wet sumping valve looks superb...looks like i will take purchase a.s.a.p......thanks to all for your quality advice....i had heard armours pipes where good...this has put me right off buying them...so i will look around for more...cheers
Title: Re: covers our street in a haze of blue smoke
Post by: a10sausage on 13.02. 2009 19:01
chrisf1....lovely bike where did you get your fenders from if you dont mind me asking
Title: Re: covers our street in a haze of blue smoke
Post by: bsa-bill on 13.02. 2009 19:33

just undone the sump drain plug and 3/4 of a pint of oil drained out.

Well that settles the discusion = glad you got to the bottom of it ( pun intended ) *smiley4*

Now we need to answer the question as to why it smokes only on one side?

All the best - Bill
Title: Re: covers our street in a haze of blue smoke
Post by: trevinoz on 16.02. 2009 05:42
A10 Sausage, fit that valve at your own peril! I have just recently seen the results of one not operating on a Norton Commando.
Crank regrind, new shells, new pistons and rebore plus a lot of labour.
If you must, fit a ball valve with a magneto cut-out.
  Trev.
Title: Re: covers our street in a haze of blue smoke
Post by: LJ. on 16.02. 2009 09:37
I must admit I am not a lover of anti sumping valves, in fact I think I would be too scared to use one, it's another part that 'can' go wrong and as Trevinoz says... "fit that valve at your own peril!"

Sausage... Now how long did it take you to undo that sump plug, let the oil run out, and then put the plug back in? Ten Mins maybe?? to help in preventing Wet sumping ensure your oil is thicker mono 50 for summers and mono 40 for winter, start and ride bike regularly at lease once a week. If you do intend to leave your bike standing for a long time then a sump full of oil is not a bad thing, the bearings will be very well oiled and with a turn over of the crank before draining you are then giving everything a good coating before initial start up. I would leave well alone...
Title: Re: covers our street in a haze of blue smoke
Post by: Chrisf1 on 16.02. 2009 12:56
Hi a10 sausage I got the fenders and stays from

AUTOCYCLE ENGINEERING
01384 253030   Fax: 01384 240401   
sales@auto-cycle.co.uk

hope this helps Chris
Title: Re: covers our street in a haze of blue smoke
Post by: a10sausage on 18.02. 2009 10:08
i almost ordered one of those anti wet sumping valves....then i thought if this thing fails it would be curtains for the engine and big wallet damage.....so i chickened out and bought an external oil filter kit from carrot cycles instead.....yes i know this kit is nothing to do with wet sumping but my friends flash has one and it performs the job well....so my next job is to fit that....i will also change my oil to 50s....i am running a multigrade at the moment....lg yes your right only 5-10 mins to drop the sump oil....and now spring is on the way the flash will be out a lot...so it might not wet sump as much......has any body got one of those magnetic sump plates...are they ok...chrisf1 thanks for the info on the fenders...thats another item on my now long shopping list..i am also in the middle of fitting an electronic ignition on my friends flash;its on of them new ones that are inside the magneto for the correct look..http://www.columbusmotorcycles.co.uk/thorspark.html (http://www.columbusmotorcycles.co.uk/thorspark.html)..report to follow....roll on the stafford show in april........the sausage!
Title: Re: covers our street in a haze of blue smoke
Post by: olev on 18.02. 2009 11:23
Gday sausage,    (probably smoked sausage by now)
More years ago than I care to admit my mate and I owned an A10 which started to smoke like yours.
On the advice of the local mechanic we removed the sump and found a bit of <something> stuck under the ball bearing in the oil return pickup. It worked fine after we removed that until we blew the barrels off. Even then it ran with a rock jammed between the top frame tube and the rocker box ... for a while. Thinking about it you wouldn't reckon there would be enough oil in the return line to cause a problem but it worked for us. Its an easy fix and worth a look.
now about the thorspark ignition. I've been looking at it for a while. They don't give out much info do they. Do they use the battery or the primary winding in the magneto?? and can you please post a picture of the points replacement thingy.
cheers
Title: Re: covers our street in a haze of blue smoke
Post by: a10sausage on 18.02. 2009 22:31
regarding the thorspark....you have to remove the mag end cap and then slip ring and points...the pick up unit slides into position where the slip ring was...the coils ...we have mounted them in the tool box...the battery is used for power to the coils...the 3 wires from trigger unit  are wired to the - and positive on the coils and one to the negative on the battery...the positive wire from the battery runs via an ignition switch to the positive on the coils....hope this helps....i will get some pics soon!
Title: Re: covers our street in a haze of blue smoke
Post by: groily on 19.02. 2009 11:58
S'pect you'll need an Alton alternator next!
Good luck with the electronic gizmo though, probably 'better' for accurate timing and advance curve. Friend of mine's got one on another marque - and it certainly works well . . . when his charging system is working properly.
On the magnetic plug point, I put an SRM thing on the bottom of mine, with its easily removable plug (to get occasional wet-sumping oil out, and to enable me to drain the cases when changing the oil without having to disturb the plate) - and it's great. My only beef was that the thing is supplied with long shiny allen screws in place of longer replacement studs (because the alloy plate is a lot thicker than the old steel one). I made up longer studs, because I think those particular small threads in the crankcase look a bit vulnerable to going out of shape (although in this case they were actually OK). Good news is the whole plate won't have to come off often - and maybe that's why the kit comes with allen screws.
On the valve, I prefer feed-line taps with magneto earth or ignition cut-out built in, although haven't fitted one to the A as there is only rarely a problem (probably because the inaccessible ball in the inaccessible wotsit is a bit suspect). I was going to, but the plan never quite got finished. They work great on 2 of my oilier toys, which can fill a sump in relatively short order, deliver oil through to the poorly-sealed primary side and induce clutch slip on a grand scale. Best antidote is constant use . . . I try!
Good luck with whatever you do though, and hope the filter conversion turns out brilliantly. There's been a fair amount of stuff on that subject in the forum over the past year, which a search should throw up.
Title: Re: covers our street in a haze of blue smoke
Post by: BSA_54A10 on 20.02. 2009 21:20
FWIW I usually ride at the rear as most of the other members ride A series bikes which accelerate a bit faster than the old M20 which I am campaining at present.
From this vantage point I notice that after a break when all the boys have left their bikes on the side stands ( left hand side) they all smoke a fair bit from the left pipe for the first 10 minutes or so.
The riders who sit their bikes on the center stand will smoke on either side or some times both.
Some of the smoke is blue & some is white.
We have put this down to oil draining down the valve guides and either into the pot and getting burnt ( blue) or vapourising in the exhaust pipes ( white)
Title: Re: covers our street in a haze of blue smoke
Post by: snowbeard on 23.02. 2009 19:41
Hey Sausage,
I gots no help on the smoke, but it sounds like you've found the issue by now.  I have a worn guide on my right exhaust and it craps up the pipe and leaks oil out the silencer joint, but doesn't seeem to smoke badly except on a hard pull at speed. 

what i was writing for was to say that's my A10 startup that shows in the related videos for yours! :-) good company for it!
Title: Re: covers our street in a haze of blue smoke
Post by: a10sausage on 24.02. 2009 18:32
hi folks....i hope all my bsa ailments will be cured on friday....a big maintainance day.....full oil change......external oil filter kit.....front fork springs to change...and helping my mate fit his thorspark....see u soon...the sausage