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Crankshaft Locking up

Posted: Tue Jun 28, 2022 1:48 pm
by callen46
Hi all. My 1956 Bullet 350 was leaking oil from the casing and also wet sumping through a worn bronze timing bush so I stripped the engine and noticed that the drive side bearings were worn so decided to replace. Having done that now the crankshaft locks when I try to bolt the casing halves together. I am certain that the roller bearing race is in sqare and also the ball race all fitted with new shims and spacers, the timing side is as it was apart from the bronze bush, if I remove the timing side roller bearing the two halves clamp together as they should. I cannot see any runout from the shafts but I do not have a lathe to check properly, and I have also tried turning the crank with the dowles and bolts removed and see no movement from the case, if any one has any idea of what it may be I would be most gratefull.

Clive

Re: Crankshaft Locking up

Posted: Tue Jun 28, 2022 2:15 pm
by Haggis
We're the original bearing imperial or metric?
Are the new bearings imperial or metric.?

Re: Crankshaft Locking up

Posted: Tue Jun 28, 2022 4:44 pm
by Bullet Whisperer
I have encountered this and had to hone the bronze bush very lightly in order for the crank to turn freely, as the bore in the new bush was not exactly concentric to the timing side main bearing, once the bush was fitted.

Re: Crankshaft Locking up

Posted: Tue Jun 28, 2022 5:19 pm
by callen46
Thanks to both of you. Haggis the original bearings would be imperial but the CRL8 bearing is now a LRJ1J probably metric also the race is a lot thinner than the original.

Bullet Whisperer. I did hone the bush slighly so it was a snug fit on the shaft but perhaps it needs a bit more. I might try removing the bush and see if that stops the seizure if it does then I will hone it out more.

Regards

Clive

Re: Crankshaft Locking up

Posted: Wed Jun 29, 2022 1:29 pm
by callen46
Bullet Whisperer wrote:
Tue Jun 28, 2022 4:44 pm
I have encountered this and had to hone the bronze bush very lightly in order for the crank to turn freely, as the bore in the new bush was not exactly concentric to the timing side main bearing, once the bush was fitted.
You were right, removed bush and everything went together as it should, just have to reamer out the bush.
I did notice that the old bush seems to be worn more on one side.

Thank you

Clive

Re: Crankshaft Locking up

Posted: Thu Jun 30, 2022 9:31 pm
by Bullet Whisperer
Hi Clive, if you can, it might be better to try and deal with the bush while in place, as I would bet less than half of the inside circumference will be binding and the tight spots will become shiny and easy to see. I would just relieve those areas, because if you ream the entire diameter / circumference, it will increase the likelihood of oil getting past from the timing chest and giving rise to wet sumping. Regards, Paul.

Re: Crankshaft Locking up

Posted: Fri Jul 01, 2022 8:45 am
by callen46
Bullet Whisperer wrote:
Thu Jun 30, 2022 9:31 pm
Hi Clive, if you can, it might be better to try and deal with the bush while in place, as I would bet less than half of the inside circumference will be binding and the tight spots will become shiny and easy to see. I would just relieve those areas, because if you ream the entire diameter / circumference, it will increase the likelihood of oil getting past from the timing chest and giving rise to wet sumping. Regards, Paul.

Thanks for that Paul, will give it a try. Clive

Re: Crankshaft Locking up

Posted: Wed Aug 17, 2022 8:59 pm
by Lou E
I had a Series 2 interceptor with a seal leak on the exhaust cam into the points cavity. The seal recess had been machined off center by 0.040. Got a seal with a larger OD and moved the hole!