Compression #'s not good, help diagnose please!

90FoxBdy

Founding Member
Jun 17, 2000
553
0
17
Linthicum, MD
Did a compression check today after finding water in my oil.(milkshake).

1 160
2 170
3 165
4 155
5 150
6 95
7 65
8 105

I just installed new copper gaskets after blowing my stock type under boost. Actually I didnt blow them just lifted the head around #1 and #2 cylinder. Water and oil was pouring down the side. The motor never overheated. Only got up to around 200.

I used the permatex spray and threadlocker in the water jackets, also new arp studs. When running the motor there are no heating issues. Car idled for 35min in 80 degrees and got just shy of 180. (That was before i knew of the water problem). The only thing other that I noticed is that #8 cylinder shoots water out of it.

Do you think the heads did not seal, cracked head, cracked block??? Im open for all suggestions. When the heads were off I did check them with a feeler gauge and straight edge and they were fine. Thxs:flag:
 
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is the oil milky since you replaced the gaskets? if everything above the cylinders are fine, then either your rings are shot or yeah, a crack, but if your block was cracked, i'm sure there'd be oil and/or coolant leaking from said crack, or atleast milky oil.
 
I think the fact that it's spitting water out confirms that it's an issue above the pistons. It probably didn't set or you've got a crack somewhere, assuming you made sure they were level correctly. Just rip that head off, inspect the block carefully... maybe have the head magnafluxed and go over both the head and block again very carefully with a straightedge. Some cracks can be pretty much invisible to the naked eye.

Best of luck.