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Old 03-15-2012, 12:09 PM   #21
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do it warm (160F min).

and do it dry and then wet (1/2 teaspoon of oil)
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Old 03-19-2012, 01:14 AM   #22
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So if the numbers for dry are bad and then wet come up better it would leave you to believe the rings are bad? But dry is bad and wet is bad then probably something else? (bad valve/gasket/...go leak down)
Good numbers are above 150psi? Nice and even numbers more important. I'm assuming my new Craftsman Comp Tester would give close to accurate numbers.
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Old 03-19-2012, 01:21 AM   #23
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Quote:
Originally Posted by 18psi View Post
first test
1: 175
2: 140
3: 160
4: 125

To me it doesn't look good, what do you guys think?
Now me and the mad scientist have to replace the piston rings you fried.
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Old 03-19-2012, 01:42 AM   #24
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It's likely either rings or burn't valves, if its not burning oil and with those readings. it should look like 007s Austin Martin oil cloud setup behind if it is the rings, I would bet on the valves. If it was anything to do with a head gasket, it should be leaking water and very doubtful that it would be 2 cyls. 125, 140. Also 160 and 175 ain't very good either. It could be a combo of both rings and valves, otherwards just plain wore out.
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Old 03-19-2012, 11:06 AM   #25
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Quote:
Originally Posted by TorqueZombie View Post
So if the numbers for dry are bad and then wet come up better it would leave you to believe the rings are bad? But dry is bad and wet is bad then probably something else? (bad valve/gasket/...go leak down)
Good numbers are above 150psi? Nice and even numbers more important. I'm assuming my new Craftsman Comp Tester would give close to accurate numbers.
a regular compression test can only tell you if nothing is bad or something is bad--maybe rings.

if even a wet test is bad, that may not mean it's not the rings, but that they are so bad the oil drains right past.
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