Skip to main content
Gerry | Vanagon
Checking account...
← vanagon.com home · Continue the discussion in the forum
Subject:Re: Still running like crap, the saga continues - Compression Test
From:Mike
Date:Wed, 19 Mar 2008 17:43:22 -0400

Not good.  Max differential between the highest and lowest readings should
be 10%;
so 135psi X 10% = 13.5psi as the max allowable difference between the
highest and lowest cylinder readings, your MIN should be 121.5psi.  Your
lowest reading is 95psi = not good.
   Now to determine where the pressure's escaping; valve(s) or rings (or
even a cracked head).
   A differential compression (leakdown) tester will show your mechanic
where it's leaking, and then you can determine a course of action from
there.  Teardown is the other alternative.....
I'm afraid to say, but it's a probably a valve job at least, a top-end or
complete overhaul at worst.

Mike B.

----- Original Message -----
From: "BJ Feddish" <bfeddish@NETREACH.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, March 19, 2008 5:04 PM
Subject: Still running like crap, the saga continues - Compression Test

> OK, my mechanic has had my van since last Friday and he called to tell me
> it's done.  Anyway he did a allot tests and some other work. Details on
> that
> later. He said the compression varied from 95 to 135. How bad is that?
> What
> have I got a month, year, decade left on this engine?
>
> Thanks,
> Bryan
>