compression and starting

[Mike Pittinaro <mechimike@xxxxxxxxx>]

> compression.  An engine that looses compression is
> much harder to crank 
> because the energy spent in the compression stroke
> leaks out instead of 
> returning to the system during the expansion stroke.

Au contraire!  Ever take the spark plug out of a
lawnmower and pull the cord?  It'll spin like crazy! 
Same thing goes if you pull the plugs out of a 440! 
Lost compression makes the engine easier to crank. 
Why do you think people drive winter-beaters with
200,000 miles on them?  the lost compression makes
them easier to start in the cold.  Also, there's more
room for the oil between the piston and cylinder, so
the cold, thick oil will slide up there and lubricate
readily (though you lose some cappilary action with
greater space)

A rebuilt engine could conceivably have less
compression than an older, high mile engine...the
carbon builds up in the cylinder on the piston and
increases compression.  Of course, the rebuilt engine
will likely have more _consistent_ compression, from
cylinder to cylinder.

Hey...I will be going junkyard hopping this
w/e...should I watch out for any parts for you, Dimitrios?

=====
--Mike Pittinaro

My girlfriend left me
My trusty Imperial
Remains more faithful

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