Author Topic: New lay shaft bush - how tight?  (Read 943 times)

Offline roadrocket

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New lay shaft bush - how tight?
« on: 06.05. 2012 16:13 »
Hello

I have fitted a new drive side lay shaft bush, after fitting a new timing side one last year. Also the big main bearing has now been replaced. I have reamed the new bush, and the lay shaft  is turning nicely when just the shaft itself is inserted, but when I assemble the whole box, it has a tight spot when turning the sprocket by hand. It is possible to turn the box by hand, but not easily. Should I take out some more with the reamer, or let the box settle/wear in by itself? Before I changed the bush, the box was easy to turn over by hand. No I did not line ream the bushes...

Cheers, Otto in Denmark
Otto in Denmark

Offline Goldy

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Re: New lay shaft bush - how tight?
« Reply #1 on: 06.05. 2012 18:53 »
What I would do is to put some engineers blue on the shaft or try some sort of thin paste if you don't have any. Then fit only the lay shaft into the gearbox and nothing else, then fit the cover and turn the shaft to see if it still binds. If it does and you dissemble it you should be able to see the marking on the bush where it is " high" and of course if it's not binding then you know it's caused by something else.
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Offline roadrocket

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Re: New lay shaft bush - how tight?
« Reply #2 on: 06.05. 2012 20:46 »
Thanks! Though I when i reassembled the box for the umpteenth time, it freed up, and is now not binding anymore. So now for the final with gaskets and goo!

Cheers, Otto
Otto in Denmark

Offline Goldy

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Re: New lay shaft bush - how tight?
« Reply #3 on: 06.05. 2012 21:28 »
The gearbox is not complicated but there are a lot of parts that can cause it to bind, and it's not always the obvious.
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56 C12 BSA project ongoing