Would a warped head cause low compression readings?

Bluestream

Petty Officer 1st Class
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Sep 28, 2010
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As stated: Would a warped head cause low compression readings, or could the readings be normal? Using a GM 3.0L marine engine
 

mkast

Lieutenant Commander
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Nov 6, 2002
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Re: Would a warped head cause low compression readings?

Perform a cylinder leak down test.
 

Desertsky

Seaman
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Aug 25, 2010
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Re: Would a warped head cause low compression readings?

Yes, a warped head CAN cause bad compression. Like said, do a leak-down test.

A warped head can show normal compression when cold or just torqued and leak after time or when hot.
 

sw33ttooth

Chief Petty Officer
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Apr 24, 2011
Messages
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Re: Would a warped head cause low compression readings?

A warped head can show normal compression when cold or just torqued and leak after time or when hot.

ever use a cheap pan to cook with and it bends outa wack, yes it can cause that low compresion will come from either the head not torqd right, bad gasket, bad spark plug seat, wear and tear the cylinder, and is shot, or bad rings. obviously start with the easy and cheap asumption, so do leak down and that should give you a heading.
 

airdvr1227

Lieutenant Commander
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Jul 15, 2009
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Re: Would a warped head cause low compression readings?

It's not just gonna warp. Have to get pretty hot to do that to a head.
 

Bluestream

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Re: Would a warped head cause low compression readings?

It's not just gonna warp. Have to get pretty hot to do that to a head.

The PO overheated the engine with a bad impeller. Not sure how bad it overheated, but now I am getting water in the oil, and can't find the source. Doing a search I found another guy who had a warped head, and was getting oil in the water. My compression readings are good, but if the head warps when hot, that could be the issue
 

Bondo

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Re: Would a warped head cause low compression readings?

The PO overheated the engine with a bad impeller. Not sure how bad it overheated, but now I am getting water in the oil, and can't find the source. Doing a search I found another guy who had a warped head, and was getting oil in the water. My compression readings are good, but if the head warps when hot, that could be the issue

Ayuh,.. Pressurize the drained cooling passages, 'n Listen....
You should be able to Hear the Leak,..
Follow the sound to the Leak...
 

Bluestream

Petty Officer 1st Class
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Sep 28, 2010
Messages
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Re: Would a warped head cause low compression readings?

Thanks Bond-o...I am going to get into in tonight. (that's my Saturday night entertainment)
 

Bluestream

Petty Officer 1st Class
Joined
Sep 28, 2010
Messages
296
Re: Would a warped head cause low compression readings?

Ayuh,.. Pressurize the drained cooling passages, 'n Listen....
You should be able to Hear the Leak,..
Follow the sound to the Leak...

Pressurized cooling system to about 15 PSI. I could hear hissing and had small amount of air coming out of my dipstick tube. Also here an internal hiss, but not sure where. Can that be anything but a cracked block?
 
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