Bearing shell condition

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alanworland
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Re: Bearing shell condition

Post by alanworland »

As Les say's, push the shell from the non tang end it should come out fine.
I changed main and big end shells on my sidevalve with the engine in situ like this which worked well.

Alan
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dudload
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Re: Bearing shell condition

Post by dudload »

Thanks all, managed to get it out using split pin method in the manual. Was worried about something becoming jammed ask the way through though!

On main bearing journal clearance, should the feller go all the way down to the crank or just the outer edge of bearing case when measuring?

Good news is the clearance is much tighter with new thrust washers though!
philthehill
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Re: Bearing shell condition

Post by philthehill »

Well done for using the split pin method of shell removal.

dudload
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Re: Bearing shell condition

Post by dudload »

thanks Phil. with the new thrust washers installed there's now no backwards/forwards movement when i try and pull/push the crank, which (i think!) is good news.

when using the feeler gauge, should the feeler be able to go past the inner raised part of the crank down to the journal, or just slide in between the upper (less protruding) part of the crank and the shell case?
philthehill
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Re: Bearing shell condition

Post by philthehill »

It is very difficult to feel 0.003" crank float when moving the crank by hand.
You should be able to insert the feeler gauge between the thrust washer and the web of the crankshaft. At a pinch you can measure the end float with the centre main bearing cap off providing that both top and bottom thrust washers are the same thickness. Having the cap off make for easier insertion of the feeler gauge between top thrust washer and crank web.
Once the centre cap is fitted and no tightness is felt when turning the crankshaft all will be well.

dudload
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Re: Bearing shell condition

Post by dudload »

Job done! Getting the sump on was a total pain - assume that the cork gaskets needed to be trimmed a fair bit as they were about a half in protrudong either side.

Turned over the engine on the handle with sparks put a few times to get the oil through the journals and then fired it up!

Was disappointed to hear the rattle there when it first started up, but this seemed to disappear after it settled down. Needs a bit of welding on the chassis leg, so will see how it runs through the black wall tunnel down to lmg Kent!

Weirdly, the centre top main bearing shell was nowhere near as worn as the lower main. Pic below - this usual?
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philthehill
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Re: Bearing shell condition

Post by philthehill »

Did you prime the oil pump before starting the engine? It is most important that you do.
The bottom shell bearing is subject to more loading than the top shell bearing so it is no surprise to see more wear occurring on the bottom bearing shell.

dudload
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Re: Bearing shell condition

Post by dudload »

Hi Phil,

Yup, I turned the engine over by hand with starter handle for about 1m before firing up, so I thought that would prime it. The oil pressure went straight to 60 upon firing up, so seems that it got oil very quickly if I hadn't primed correctly.

Had a horrible, horrible realisation that I only did the oil pickup nut to finger tight (put it on first before doing up the bolts) late last night. So, sump all back in off to tighten it up! Very frustrating as I went around each bolt ensuring lock tab is on before putting back together, forgetting the one non-bolt! Especially as my absolute least favourite part of the job was removing, and especially reinstalling, the sump - the thing was a nightmare to get on!

(Assume new gasket required, even if only in situ for a couple days, as will be fixing Saturday?)
philthehill
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Re: Bearing shell condition

Post by philthehill »

Well done for priming the oil pump.
Luckily you remembered that nut. If not tight you could be sucking air into the pump and not oil. Dredd to think of what could have happened if the nut had come loose and dropped down onto the filter and you lost all pump suck.
If the gaskets are greased before fitting there is no real problem with reusing the gasket as the grease will have kept the gasket supple.

dudload
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Re: Bearing shell condition

Post by dudload »

good stuff - maybe there was a fraction of a sec with low oil pressure that caused the rattle, but confident it got it quickly after my priming.

Yes - remembered about that nut whilst falling asleep (when i do most of my thinking :D ) Can't bear the thought of having to redrain oil and removing those horrendous fiddly sump bolts again - just after i'd packed all my tools away in a smug manner. good news that the gaskets are resusable though - there were coated in a good layer of grease on both sides, mostly to get it to stick in the right place on the block when presenting the sump!
oliver90owner
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Re: Bearing shell condition

Post by oliver90owner »

Plugs out and wound round on the starter motor is my usual way of checking that oil pressure is good, before starting a fresh rebuild.
philthehill
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Re: Bearing shell condition

Post by philthehill »

When starting my1380cc engine after being idle for a while I remove the plugs, disconnect the remote oil filter pipe at the block end and back fill the oil pump through that connector. When the pump is full (after giving a couple of turns on the crankshaft) and will not take anymore oil - I reconnect the pipe then give the engine a spin on the starter and the oil pressure comes up straight away.

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