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Engine full of fuel and seized up

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PJM47:
yes what I thought. That centre one is the worst case and I will replace the pair. I was hoping to avoid having to replace them all though as they are so expensive, but maybe it's worth doing now. What seems like a no brainer job on this bike is always a hesitation as everything is so expensive. 
If anyone has a source of bearings cheaper than £15 a shell that would be good :)
I think I have worked out the codes, BABBB on the case and AAAAA on the crank so I make that 4 greens and a yellow.

Big end bearings all look pretty good, much better than the mains.

paul G:
I got mine from Yamiya, Cheaper than Silvers even with post and capture duties😉

McCabe-Thiele (Ted):

--- Quote from: PJM47 on October 24, 2020, 04:23:18 PM ---yes what I thought. That centre one is the worst case and I will replace the pair. I was hoping to avoid having to replace them all though as they are so expensive, but maybe it's worth doing now. What seems like a no brainer job on this bike is always a hesitation as everything is so expensive. 
If anyone has a source of bearings cheaper than £15 a shell that would be good :)
I think I have worked out the codes, BABBB on the case and AAAAA on the crank so I make that 4 greens and a yellow.

Big end bearings all look pretty good, much better than the mains.

--- End quote ---

When I worked on petrol engines (mainy on cars admittedly)  it was pretty much routine that a crank removal led to replacing the crank & main shells. Even when the bearings didn't look that bad it was a case of well my labour is free so why skimp on the material costs bearing in mind the amount of effort involved in dismantling the engine again.

I also found that replacing piston rings under the same argument was not as effective unless there was a very good reason such as poor compression, visible damage such as a broken ring or piston lands plus of course bore scoring / excessive oil consumption.

Likewise I have never been a fan of glazebreakers after over doing it once resulting in needing a rebore. I would prefer to have a rebore if the aforementioned issues were found. I also learnt to my cost that there was a wide range of competency in machine shops that did rebores. In the 1970's there were something like 8 or 9 firms in the Derby area that carried out engine machine work. Some firms seemed to live on reputations that were not maintained over time.

If I have to have a rebore on my bike I would struggle to know anywhere locally as I am now out of the circle of local knowledge - I haven't had an engine rebore since 1979. Irrespective of the distance from me I would in all honesty place my trust in someone such as Trigger as he has what I perceive as that rare combination of reputation, skill, pride in his work with a love of what he does.

Bryanj:
You are correct in that getting a decent rebore nowadays is difficult, probably due to the eliability of modern car engines compared to the old Vauxhaul and Ford units, hate to think how may Kent and Essex lumps i have rebuilt in my life and yes with cars not changing shells was a stupid idea but then a full set of Kent shells cost the same as 1 journal for a sohc 4, having said that i would not even consider replacing just one journal, it has to be a full set

philward:
Had a 1200 Anglia that had a 'rubber crank' - 3 main bearings - centre bearing always knackered (was that a Kent or Essex or none at all?)

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