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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

Compression Test/Coolant in exhaust

  • Thread starter Thread starter RangerJoe
  • Start date Start date Feb 27, 2011

RangerJoe

I leave the horn on while driving
15 Year Member
Apr 26, 2010
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Feb 27, 2011
#1
  • Feb 27, 2011
  • #1
Ok, here is a long post. Just built new 331 stroker. Block was decked and heads were milled .015 for clean up (iron gt40). Compression is about 10.15:1. Edelbrock Performer Intake.

Motor has not been broken in yet. It has been cranked up about 5 or 6 times, ran for a total of probably 20-25 minutes trying to work out idle and such so it could be driven. Noticed small puddles at exhaust pipes, watched for a little while and realized that it was more than condensation. Pulled upper intake, it looked like I was dripping antifreeze into the end cylinders. Pulled intake, re-installed, bigger puddles. Went back, redid gaskets with red gasket maker around coolant ports, changed oil. I haven't tried to restart it yet and see if it still leaks.

I ran a compression test on the cylinders and a compression test on the coolant system. I pumped the coolant system up to 16#. After about 20 minutes it falls about 1#. I don't see coolant in the intake runners (I have the upper intake off at the moment). I have found a few leaks in hoses, etc, been fixing them as I go.

My compression test are crappy. I can't get more than about 25# on any cylinder with the dry test, and with the wet test I get about 50#. Is this normal? I know the rings are not set to the bore walls yet, but would it let this much by?

Intake is torqued to 25# in the "proper" sequence. I did compression test with plugs out of heads.

Any ideas?

Thanks
 

5.0Droptop

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Feb 27, 2011
#2
  • Feb 27, 2011
  • #2
Make sure you go over the tq sequence several times untill the lower intake seats all the way down and stays tight.

As for compression. If your rockers are adjustable you may have them to tight and the valves may not be closing all the way
 
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