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Vacuum both PVC's to intake?

Vacuum both PVC's to intake?
Dry compression numbers are: 1 - up front, thru 6 - in back

1 - AMC 150
2 - 152
3 - 157
4 - 176 - (Yup, tested it twice)
5 - 155
6 - 152

After getting the above, i retested 4 to verify that I didn't do something wrong and got 173 the second time.

Thoughts? :confused: Do I have one good cylinder and 5 bad? :roll eyes: Likely it seems.

Again, all of these are dry test, didn't have oil with me to do a wet test, but not sure if it's needed.
 
Those numbers seem OK to me, Triman. AMC 150 is in spec, dry. The 176 is puzzling. Seems a bit high. Someone might have replaced one piston set before you got it. Maybe a whole piston.

Are you confident the gauge is accurate? Not sure if you have access to air fittings and whatnot, but hooking up the gauge to a compressed air line of a known pressure is a simple way to check it.

I personally never saw a gauge inaccurate enough to put the numbers you posted into the "rebuild time" pressures.

I'd try the suggestion earlier of using a push-in crankcase breather. If Oil Fog doesn't cover everything, keep running with it.

With those compression numbers, nothing jumps out as a red flag to me. Compression Rings seem O.K.

Years of service left, OK.

Oil Control rings, maybe not. Don't sweat it. Worn Oil Control rings just require a little more attention to the Dipstick, and Spark Plugs.

And remember to cap off the vacuum port the PCV was on.
 
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