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TR2/3/3A New head gasket is installed.....did a compression check motor cold.

karls59tr

Obi Wan
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I got 180 psi in all cylinders but this may have been because I put more oil in the cylinders than I probably should have....maybe 1/2 a shot glass worth? I'm not going to start the car until it's at least 10 Celcius here. I will let it warm up before I do another test. I'll bet it's going to smoke. Isn't 145 psi what it's supposed to read? Is my compression tester out of whack??
 
Absolute compression values are almost meaningless. The fact that they match, between the cylinders, is most important.

All the compression testers I've seen, today, have the valve right at the gauge. Then, there is a piece of tubing or even a long hose connecting the gauge to the cylinder. The volume of that hose adds to the cylinder volume, so the compression value depends on that hose. When I was young, a loooong time ago, I had a compression tester with a rubber nipple that fit into the spark-plug hole, and the valve was in the end of that nipple. That's the way to do it, but I haven't seen a tester like that in a long time.

But this effect makes the reading lower, not greater, so if you are seeing a uniform 180 psi, I think you are in good shape.
 
If you are worried about it being higher, no need. Adding oil will do that. This is the engine that had the coolant leak?
 
If you are worried about it being higher, no need. Adding oil will do that. This is the engine that had the coolant leak?
Yes the engine with the coolant leak. I'm happy about the high and consistent compression readings. Good weather next week so I'll fire the engine up then and report. (y)
 
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