Author Topic: '48 LS Engine rebuild  (Read 663 times)

Offline fffcycles

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Re: '48 LS Engine rebuild
« Reply #15 on: 21.04. 2021 01:32 »
I have quite a few other BSA cranks, amongst others, and never seen anything like this before. Everything I learned in my electro-mechanical career says there must be an even supply of oil to maintain the oil dam and film effect for good bearing performance.
Could’ve someone’s thoughts on balancing flow on this but we will see.
Frank
Frank P
1948 A7 Long Stroke, a collection of BSA D1/B44/B50/A65 from the 50's thru 70's, Ariels/Nortons/Triumphs and a smattering of Japanese

Offline fido

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Re: '48 LS Engine rebuild
« Reply #16 on: 22.04. 2021 12:55 »
How were the little ends? One of mine is a bit stiff so I will need to find someone with a reamer. There are scuff marks on the piston but I think they will polish out. I previously had a short stroke A7 and the thing that stuck me  with the long stroke is the much smaller cam followers. They seem to work OK though as the cam and followers are in good condition. I had to renew the followers on the short stroke as they were well worn on the contact faces with the cam.

Online chaterlea25

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Re: '48 LS Engine rebuild
« Reply #17 on: 22.04. 2021 13:42 »
Hi,
A Monday morning or Friday evening job??
If it was intentional to not have the hole there they would not have ground the relief in the journal...
A few years ago I saw sorting out a C15T and found the breather hole in the cam bush/ timing case had never been drilled
No wonder I ***** oil out every joint on the engine

John
1961 Super Rocket
1963 RGS (ongoing)

Offline fffcycles

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Re: '48 LS Engine rebuild
« Reply #18 on: 22.04. 2021 15:46 »
Small ends are fine and thus should go together without any more drama, I hope.
Yeah, football was on the telly and Clive wanted to get home on time! Fixed now and just have to drop in and pick it up.
Frank
Frank P
1948 A7 Long Stroke, a collection of BSA D1/B44/B50/A65 from the 50's thru 70's, Ariels/Nortons/Triumphs and a smattering of Japanese

Offline fffcycles

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Re: '48 LS Engine rebuild
« Reply #19 on: 02.05. 2021 14:59 »
Another few days of work and I now have the crankcase tightened up but as I got the bolts done up it is now very hard to rotate the crank. Oh well, guess I take it apart pull the bearing and take the .010” spacer out then reassemble again.
First time doing this particular style of engine but not unexpected.
Meanwhile good weather and the Norton have kept a smile on my face.
Frank
Frank P
1948 A7 Long Stroke, a collection of BSA D1/B44/B50/A65 from the 50's thru 70's, Ariels/Nortons/Triumphs and a smattering of Japanese

Offline Swarfcut

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Re: '48 LS Engine rebuild
« Reply #20 on: 02.05. 2021 17:28 »
 Fit the drive sleeve and retaining nut. Tighten down hard with a peg spanner.  This will settle the ball race against the crank. May save dismantling if the race moves towards the crank.

 Swarfy.

Offline fffcycles

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Re: '48 LS Engine rebuild
« Reply #21 on: 03.05. 2021 15:42 »
Good advice, did not give me much, so crank moved but with the help of a strap wrench. Not the worst job and I have the tools so half an hour I have it apart then it is just chilling and heating to get everything back in place.
The bushing thrust face is only showing a rub mark in one small area so might just pop that out and check if it is machined correctly as this is one of the plain bronze types and is a little thicker at 0.135” compared with 0.125” for the steel sleeve ones I have as well. That would make a world of difference taking that down as an alternative to taking the bearing off again.
Frank
Frank P
1948 A7 Long Stroke, a collection of BSA D1/B44/B50/A65 from the 50's thru 70's, Ariels/Nortons/Triumphs and a smattering of Japanese