Paul,
I would start by removing one piston and then its top ring. Place the ring
back in the bore and determine its 'gap', i.e. the distance from one end of
the ring to the other. I don't know what the recommended gap should be for
your engine but it'll be in the workshop manual. Then check all the other
rings. If they're OK, measure the pistons, both fore and aft and crossways.
They won't be round they're oval but you'll be able to measure the clearance
and check it against the book.
If the gaps are OK then I'd check all the bearings with 'plastigauge'. Its
like fine plastic string that you squish between the crank and the bearing,
and then measure its width. The bearing clearance should be one & a half to
two thousandths for each inch of diameter. You buy the stuff at any parts
store.
Cheers and good luck, "Bob".
> From: "Kerr, Paul AAF:EX" <Paul.Kerr@gems7.gov.bc.ca>
> Reply-To: "Kerr, Paul AAF:EX" <Paul.Kerr@gems7.gov.bc.ca>
> Date: Wed, 17 Jan 2001 15:35:46 -0800
> To: british-cars@autox.team.net
> Subject: refitting pistons
>
> listers - I am in the process of refitting the pistons in my 72 Midget. new
> rings were supplied and fitted by a local specialist who did the valves for
> me. This shop also supplied the new big end bearings.
>
> I have completed reinstalling the pistons and fitted the new bearings,
> lubricating everything as a went.
>
> I am now wondering how stiff the pistons should be and how difficult the
> crank should be to turn over. With the new rings I expected it would all
> feel a little tighter, but now I find it very difficult to turn the crank.
> Surely it shouldn't be this tight?
>
> Any suggestions as to what the problem might be - i.e. what I have screwed
> up?
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