Date: Tue, 17 Mar 2009 18:50:49 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Low compression results accurate?
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a cold compression test like that, on an engine that's been sitting , will
always read lowish.
Not a valid test really.
it's probably true that it ran fine, and the compression is really more like
100 t0 120 as a wild guess...
which is still only 'sorta ok', not stellar.
you should *at least* put some oil in each cylinder..........then crank it
with all the plugs removed.....
that'll help get oil into the rings helping them seal better.
for 'dead engines' I like a leak down test. Doesn't depend on starter
cranking speed.
if you were closer I'd want the auto trans.
a 2.1 block with fit where a 1.9 one was......but there's some swapping over
of parts, mainly cooling system.
and one small mod to the intake plenum/box thing on top of the engine.
you can use either exhaust system ......the 2.1 is better.
you can also convert your 85 to 2.1 cooling system..........and fuel
injection system ...........I did that to my 85 Wolfsburg weekender.
You need some cooling system parts from the 90 body to do that to your 85 .
Scott
www.turbovans.com
----- Original Message -----
From: "Edward Duntz" <eduntz@HOTMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, March 17, 2009 12:38 PM
Subject: Low compression results accurate?
>I went to look at a partially-disassembled Vanagon yesterday to use for its
> engine in my tired '85. The parts van ('90 with auto trans and 2.1)) had a
> lot removed, including the computer, distributor, and battery. I wanted to
> do a compression test on it- the starter and transmission were still
> connected. I hooked up jumper cables- positive on my battery to the big
> terminal on the parts van starter; negative on my battery to the
> transmission on the parts van; and a jumper wire from the big starter
> terminal to the spade terminal on the solenoid. Each time I wanted to
> crank
> the engine, I held the terminal onto my positive battery terminal.
>
> I got readings of between 80 and 90 psi on each cylinder. The results I
> got
> seemed too low to be accurate, so I was wondering if there was something
> else in the situation that could cause results so low. Obviously the
> engine
> had not been at operating temp before the test was done, but I couldn't
> control that. The starter did crank slowly, but I let it turn over enough
> until the gauge didn't rise any more.
>
> The owner said the engine had run fine and had power on the highway. I
> suppose that you can get up to highway speeds even with low compression,
> albeit very slowly. But would it even start and run with compression so
> low?
>
> I wanted this engine to put in my '85. I could take the whole van 9what's
> left of it) for a decent price and maybe part out the rest of it, but I
> really wanted it for the engine.
>
> Thanks for any advice,
> Ed in CT