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Re: compression test question

To: "Elton Clark" <lotus.tony@airmail.net>
Subject: Re: compression test question
From: David Scheidt <dmschei@attglobal.net>
Date: Sun, 2 May 2004 17:11:08 -0500
On May 2, 2004, at 4:52 PM, Elton Clark wrote:

>
>
>> What's it mean when you add oil to the cylinder, and the compression
>> goes *down*?   The engine in question is in a Ford 8n tractor.
>
> Some smarty-pants is gonna say your gauge broke but I bet there's more 
> to
> the story:
>
> What was the #psi reading before and after?

95ish pre oil, 85 ish after.  (Two tests each time, consistent numbers.)

>
> Did this happen on all cylinders?

>
> were the throttle & choke open on both tests?
>
> How much oil per cylinder?

> Did the starter turn equal speed?
>
> Did you give each test equal "hits?"
>
> What condition does the engine seem to be in otherwise?
>
> Has anything changed valve timing?
>
> Can you do a "leak-down" test, borrow a tester, etc.?
>

It's just the number four cylinder.  All  the other cylinders had their 
compression shoot up (20  or 25 %), which is what I expected.  The 
engine is pretty well worn out.   It's going to get torn down this 
summer, and get whatever it needs.  So it doesn't really matter.  It's 
just that I've never seen an engine do that.






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