Compression problem? - Diesel Forum -
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post #1 of 4 (permalink) Old 08-08-2005, 05:57 PM Thread Starter
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Compression problem?

Thanks all for help last couple of post.

Can any one give me the Steps and advice on removing the heads on 7.3 IDI to check them and find out why #8 has 0 Compression?

Thanks to all.

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post #2 of 4 (permalink) Old 08-08-2005, 07:45 PM
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Re: Compression problem?

Mel (agnem) has a great Article on removing the heads for head gasket replacment. But, that will still apply to taking the heads off. Be sure to remove the head in reverse torque sequence, otherwise, you could warp or crack the heads! [img]/ubbthreads/images/graemlins/eek.gif[/img] [img]/ubbthreads/images/graemlins/vomit.gif[/img] If you don't have a manual (like Haynes) that gives you the sequence, some one on the site will have a link to it for you.

Did you find any problems when you removed the valve covers? Keep us up to date on what you find.


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post #3 of 4 (permalink) Old 08-08-2005, 09:20 PM
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Re: Compression problem?

I would exhaust all other possibilities, before removing the heads.
It does not sound correct, 1 cylinder having 0 compression, and no other symptoms.

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post #4 of 4 (permalink) Old 08-08-2005, 09:33 PM
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Re: Compression problem?

I'm with Bob on this one, dig around until all possible causes are exhausted before doing the head(s). Keep us up to date as to what you find it may tweek someone's memory reading your posted info...

Really not rocket science but there is a different tone of each valve when the stem is tapped with a hammer and it reseats, due to one being bigger than the other do two exhaust valves ie 6 and 8 then the two intake valves. The valves should sound the same ie both intakes, then both exhausts. If you get one set with a different sound of the same type valve that could isolate the problem a little.

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