The BSA A7-A10 Forum
Technical (Descriptive Topic Titles - Stay on Topic) => A7 & A10 Engine => Topic started by: sixpak on 19.03. 2017 22:13
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I am really desperate....
https://youtu.be/BBI5vqqgIOs (https://youtu.be/BBI5vqqgIOs)
https://youtu.be/yYLRhYJRJkQ
(https://youtu.be/yYLRhYJRJkQ)
Can anybody tell me whats going on here?
Who can organize a new good (maybe fast) engine for me?
adm edit: edited topic title to reflect content
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This looks like oil leaking from the rocker box onto the exhaust header. I don't see excessive smoke from the silencer. Am I wrong about that?
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what i know, if i unplug the spark plugs and look into the cylinder i see oil drop on top of piston
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Looks like she's got a few leaks there buddy.. *conf2*
Do you KNOW the history of the bike?
1. Has the motor been rebuilt? 2. If so by who & when? 3. has the head been re-torqued since build?
If possible ask the previous owner these questions? She may only need a couple of new gaskets & re torquing? *????*
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?? head gasket - valve guide - piston rings ??
If lucky, wrong head bolts torque setting. I'd start with checking that. If ok, then it's on to remove top and cylinder.
btw, nice oil tank return view :O)
Who can organize a new good (maybe fast) engine for me?
You (with a little help from forum members :O)
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i am familiar with flatties ford and chrysler engines
not bike engines
but i am interested to learn...
but massive vibrations tooo... when bike is idling... its walking *smile* *smile* *smile*
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Im going to guess all that smoke is a leak at the rocker box like Mr. GB mentioned.
Your not getting smoke at the exhaust that can been seen in the video, so Im going to hope its all external.
More unsettling was the exhaust coming from under the motor. I cant tell if thats coming from the breather or from the case joint or what the deal is there.
Vibration isnt helped by that motor mount system either I would not think.
Lee
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Just watched the video again a few times.
How hot is that motor???? It looks like something is boiling (bubbling) in the very quick portion showing underneath....
Lee
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what i know, if i unplug the spark plugs and look into the cylinder i see oil drop on top of piston
That may be an important clue. But there's the (seemingly) lack of blue smoke from exhaust. And the 'blowout' from under the engine is ...interesting :0)
But to check for possible leak from rocker cover, should be very visible, clean thoroughly, then start it up an watch carefully.
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Just a wild guess, but;
As has already been suggested, I'd go for head-bolt tension or blown gasket.
If it's real untight , (especially at the front), compression could blow the oil from the rocker return gallery out onto the exhausts and also up into the rockerbox to create excess crankcase pressure and blow oil out the breather underneath.
*dunno*
Walking on the Centre stand is fairly normal; well, mine does it
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well i thought it sounded ok. they always smoke a bit until the gasket grease burns off. if oil is pouring out of one exhaust it could indicate a loose valve guide. yes, you have an oil leak but oil is not pouring over the back wheel. clean up the engine and go for short rides until you find the source of the leak. you will save a lot of oil leak problems if you carefully assemble everything with wellseal, including the head gasket.
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The amount of gases coming out of the breather pipe (assuming that is being shown in the underneath view) indicates a (new) top end problem, assuming the engine was ok beforehand, the new issue could be just a blown head gasket, if so, that could also explain the oil burning off the cylinder head area, as either oil is leaking onto the fins from the pushrod tunnel/tube as a result of the head gasket leak, or a rocker box gasket is leaking onto the fins caused by the head gasket increasing the crank case pressure.
Engine sounds ok, but you should know more when the head is off.
You might be able to verify a blown head gasket by slowly turning the engine over by hand and listening for hissing noises!
You MIGHT be lucky if you have a solid copper head gasket and you have the option of trying to fix it by simply re torquing the head bolts but more likely a top end strip down is needed.
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as well as the above and even tho the oil return is working fine, if its been sitting for a while could it just be wet sumping and forcing the oil out everywhere? (breather, head etc). if you want to check remove the sump (or just the bung if it has a modern sump) and check - should be about half a cup in there. lots more than that is a problem.
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good morning... thx for all that tips.. very interesting, since i buyed the bike just a week ago, i cant really say how new the problem is, but i really have to check...
can you please tell me more about the engine mount problem you mentoined?
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can you please tell me more about the engine mount problem you mentoined?
It's not really a problem, just the way it is, but I don't have a problem with it (just a bit vibie)
IE;
Vibration isnt helped by that motor mount system either I would not think.
You MIGHT be lucky if you have a solid copper head gasket and you have the option of trying to fix it by simply re torquing the head bolts but more likely a top end strip down is needed.
Might be almost the same lucky if it's a blown composite one that can be replaced with a TTJohn (?) solid copper one *smile*
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G'day sixpac.
Wet sumping will cause excess fumes & oil out the breather (what you see under the motor) and cause other oil leaks. It should clear after 5 minutes or so. As Mike said, drop the sump plate or drain bolt if fitted. If that doesn't help and there is still excess fumes and oil from the breather leads to rings not bed in and/or head gasket leak
As said the lack of smoke out the r/h pipe is puzzling if there is oil on the piston. The smoke off the pipe is more than likely rockerbox leak but that pipe does look as if it's getting hotter than the other.
Drain the sump, give it all a good clean and run her for a few minutes looking for rockerbox leaks and any reduction in breather fumes. Report back.
Cheers
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thank you very much, i will do so... have to find out how to open that sump thing... ;)
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The standard sump plate is held with 4 quarter" cycle nuts. you may have to give it a few gentle taps with a knockometer. The after market alloy plates have a drain plug.
Cheers
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Hi sixpack,
If you go for the SRM type sump you will need longer studs in there. Don't use bolts as they wear the threads in the crankcase. I use rocker cover studs that do the job nicely.
ELLIS
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The 30 second video shows he's got a SRM type with the drain plug..
17mm ring spanner anti clockwise .. *smile*
Is the Right hand pipe all the way into the head?
it looks like it's out a little & exhaust gasses are blowing past?
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what i know, if i unplug the spark plugs and look into the cylinder i see oil drop on top of piston
Might this just be oil running off the head and into the plug hole when you take the plug out?
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It might just be the video but as previously mentioned it seems to be running very hot. This would cause oil to leak especially from the top end, it certainly did on my Huntmaster. Mine only runs at a normal temperature using premium fuel and a lead replacement / octane booster additive. Without this it pinks and overheats on modern fuels.
Check the ignition timing, too far retarded will cause hot running. Also remember the engine doesn't want to be left ticking over too long, this also will cause it to get too hot.
Colin
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Hi Sixpack.
Very nice bike. IMHO I reckon you should get the head off and check it out.
I also bought a great looking bike but there is no way to know the condition of the internals.
It's yours now and the journey has just begun.
You will find that taking the head off is just a lazy night in the shed to check out what state it is in.
I had a similar problem and found sloppy valve guides which I replaced and while I was at it, I decided to reco the head.
As I don't do many km's this will probably last for as long as I own the bike.
Well worth it.
Kind regards, Hadrian.
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i did it yesterday... it was... a mess!!!!!!!
i am pretty shure wrong head bolts, overtorqued or not torqued, piston scratches the wall, wrong valve measurements, totally mess!!! Pushrod broken at top and more... its a mess completly
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i did it yesterday... it was... a mess!!!!!!!
i am pretty shure wrong head bolts, overtorqued or not torqued, piston scratches the wall, wrong valve measurements, totally mess!!! Pushrod broken at top and more... its a mess completly
Sorry to hear that, unfortunately many of our bikes are restored or rebuilt by amateurs, some are better than any professional, some not, it's a lottery when you buy a bike particularly if there is a history of recent major work, on the upside, with the help of this forum you will be able to put things right, as good if not better than new *smile*
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i did it yesterday... it was... a mess!!!!!!!
i am pretty shure wrong head bolts, overtorqued or not torqued, piston scratches the wall, wrong valve measurements, totally mess!!! Pushrod broken at top and more... its a mess completly
*cry*
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thx alot, first of all al i will look for a new balanced rotating assembly with oversize pistons one more then +.040, and maybe a cylinder and aluminum head...
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That's a bitch sixpack, maybe a good learning curve for you AND your girl buddy to come help- with a sixpack *beer* or ten *eek*
I like to say it's a straightforward operation, but totally dependent on parts availability... having said that everything might clean up reasonably ok and defer any inevitable until after your riding season *dunno* *beer* *beer*
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you think its not possible to get a rotating assembly?
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You'll have to be very lucky to find a crank, rods and the correct size pistons as a 'good' assembly, ready to fit.
Sometimes it's a problem to find individual parts.
But - you're in the right place here. I have been helped enormously by fellow members (tx, you know who you are!).
Good luck!
Post a 'wanted' thread with very specific details of what you think you need.
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Sixpack,
It seems that you are in for a complete strip-down, inspection and rebuild, if you're up for it. First advice is to take it slow or, at least, carefully. As for riding this season, I suppose that's dependent on how much time and money you can devote to the job. Are you anywhere near Aadorf? Our member, Peter, lives there and may be some help to you. You can check the member list and send him a personal message or email. I assume you are aware of British Only Austria. Vintage-motorcycle.com.
Now, do you have the Haynes manual for A10s and a parts book for the year of your bike? If not, I'd say get those and browse through them thoroughly. The Haynes book is not perfect, but it's about all there is for a step-by-manual. Folks here can clarify as needed.
As for the things that rotate, the first step is determine where the crankshaft is in its life. Another recent thread here has gone through the measurement necessities of that and we can steer you there if needed.
Well, my train is pulling into the station, so must sign off.
Richard L.
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Aadorf is around the corner...
thank you i am very thankful for all the cares and inputs.. since i did many us cars, i understand quit a bit of that stuff, but this is another speciality.. i want to put much effort in it, since i want to drive, have other project sitting around...