RE: Compression test

["TJ Noto" <tj@domain.elided>]

Your thinking is not entirely wrong (oil does have an effect on
compression and other vital engine functions) Mark but there's no way
oil around the rings (where it does its sealing) would drain down the
cylinder walls.  Oil captive in the ring grooves and on the rings
themselves will stay there for a very long time.  It's simply too small
an amount to appreciably "drain" off.

The usual trick is that a few squirts of oil in to the combustion
chamber will usually bring compression up after an earlier test reveals
low compression.  It's basically a method of isolating valves from rings
as the culprit for low compression.



TJ

TJ Noto		AFM #134  	Cowpoke Racing-"Friends in Slow Places"
http://www.cowpokeracing.com
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> -----Original Message-----
> From: owner-alfa@domain.elided [mailto:owner-alfa@domain.elided] On Behalf
Of
> Mark Denovich
> Sent: Tuesday, January 21, 2003 10:05 PM
> To: Alfa Digest
> Subject: Re: Compression test
> 
> AlfaNeely@domain.elided wrote:
> >        Nothing wrong with testing a cold engine that has sat a
while.
> >  Results might not be quite as accurate, but comparisons across the
> > cylinders should still be valid.
> >       Why do you think otherwise?  Engine parts are not going to
shrink
> > all the much in the cold.
> 
> My thinking is that oil plays a signifcant part in the sealing
equation.
> After sitting for a while the oil would drain away, possibly in an
> uneven matter...  thereby making the compresion readings less
accurate.
> 
> 	--Mark
> 	http://alfa.denovich.org
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