I have now stripped the engine on the '65 BSA C15 wreck I bought. Some ugly sights on the way...
Primary cover off and I found the primary chain rusted and seized solid. Made a clutch hub puller on the lathe and with a 3 leg puller on the engine sprocket, it came off after some swearing.
The contact breaker and backplate may need replacing
'
It looked pretty nasty under the outer timing cover too, but will all clean up. May be able to restore the auto advance unit.
Under the inner cover, it was even uglier....... although the gear cluster all seems good. A sort of brown blackcurrant jam was still in the gearbox which had protected the parts from corrosion......
Surprisingly, the engine was not seized, but the bore was well scored.
Two broken lower fins on the cylinder head, several stripped threads.
The rocker box is OK, except that Japanese rocker box caps had been forced into the original different threaded holes. Pushrods are scrap (welded up non-original things). Pushrod tube is in poor shape and the sparkplug hole in the head has had a home made steel insert put in and the internal thread is way off round.
The engine was loose in the frame anyway, wrong bolts, no bolts and a seriously broken crankcase mount bracket at the front.
The crankcase halves split easily enough. The drive side crank main roller will need replacing and the timing side main bush too.
The piston is Italian and not too bad but the big end is worn out with too much play. Note the welded up gearbox sprocket. The sprocket was worn out and someone had cut the old teeth off, then welded a new ring of teeth onto the original splined centre.
That's the engine out for refurbish and/or replacement of parts and re-assembly.
I made some pushers and holder to get the sleeve pressed out of the barrel at a local car shop.
You could read the history.... the barrel had been overbored a few times and was at about maximum and then there had been a catastrophic failure (probably a home made gudgeon pin circlip had come loose). The scoring on the original bore is clear. Then a sleeve had been made and fitted, so the bore was back to about original 67mm diameter.
The crankshaft sludge trap was blocked solid.
I made some press plates to split the crank, back to the car shop again.
Some of the rollers were home made and one looked like a piece of stainless steel rod, undersize by 0.5mm. The conrod bush and the crankpin also had some wear.
So now, begins the nicer part. working out what parts needs replacing and what needs restoration work. It will be a fun project.
Primary cover off and I found the primary chain rusted and seized solid. Made a clutch hub puller on the lathe and with a 3 leg puller on the engine sprocket, it came off after some swearing.
The contact breaker and backplate may need replacing
'
It looked pretty nasty under the outer timing cover too, but will all clean up. May be able to restore the auto advance unit.
Under the inner cover, it was even uglier....... although the gear cluster all seems good. A sort of brown blackcurrant jam was still in the gearbox which had protected the parts from corrosion......
Surprisingly, the engine was not seized, but the bore was well scored.
Two broken lower fins on the cylinder head, several stripped threads.
The rocker box is OK, except that Japanese rocker box caps had been forced into the original different threaded holes. Pushrods are scrap (welded up non-original things). Pushrod tube is in poor shape and the sparkplug hole in the head has had a home made steel insert put in and the internal thread is way off round.
The engine was loose in the frame anyway, wrong bolts, no bolts and a seriously broken crankcase mount bracket at the front.
The crankcase halves split easily enough. The drive side crank main roller will need replacing and the timing side main bush too.
The piston is Italian and not too bad but the big end is worn out with too much play. Note the welded up gearbox sprocket. The sprocket was worn out and someone had cut the old teeth off, then welded a new ring of teeth onto the original splined centre.
That's the engine out for refurbish and/or replacement of parts and re-assembly.
I made some pushers and holder to get the sleeve pressed out of the barrel at a local car shop.
You could read the history.... the barrel had been overbored a few times and was at about maximum and then there had been a catastrophic failure (probably a home made gudgeon pin circlip had come loose). The scoring on the original bore is clear. Then a sleeve had been made and fitted, so the bore was back to about original 67mm diameter.
The crankshaft sludge trap was blocked solid.
I made some press plates to split the crank, back to the car shop again.
Some of the rollers were home made and one looked like a piece of stainless steel rod, undersize by 0.5mm. The conrod bush and the crankpin also had some wear.
So now, begins the nicer part. working out what parts needs replacing and what needs restoration work. It will be a fun project.
