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What does this compression test mean to you?

Dry:

Cyl# 1: 120

Cyl# 2: 151

Cyl# 3: 125

Cyl# 4: 102

Wet:

Cyl# 1: 200

Cyl# 2: 235

Cyl# 3: 155

Cyl# 4: 139

all of them are supposted to be atleast 150 or so.

Bad rings?

Update:

the engine only has 92k miles on it, its 42 years old though. lol

5 Answers

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  • 1 decade ago
    Favorite Answer

    Bad rings or burnt valves, burned valves will cause compression loss also. If it still runs decent keep driving it. If it does not run well and burns oil and such and you are rebuilding it then all will be good when you are finished.

    Source(s): Just my opinion, good luck
  • 1 decade ago

    All are within the variable wet, not dry. I would say with pressure up on a wet test it's rings. Oil temporarily seals the rings not the valves. Is the engine cold or warmed up this can also cause a variance in your readings. Also timing must be dead on.

  • 1 decade ago

    if there's some pressure on the oil filler cap openings,when you remove it while idling the engine,surely it is the rings on #3 & #4.we call that blow-by.(and some smoke is coming out from that openning where you pour oil). But if not, then check around the cylinder head for oil leak or moist,if you see some ,probably a gasket problem.If these all okey, then probably the valves.try using that gas treatment additives and check spark plug ,if fully tighten,you know....you might over look some simple things like that sometimes....good luck!

    Source(s): backyard mechanic!
  • 1 decade ago

    Could be or leaking around valves, or weak head gasket. Carbon build up on valve seats can cause leaking compression as valves are not seating correctly. Run a good fuel injection cleaner through and retest.

    Edit: What's the engine mileage?

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  • Anonymous
    1 decade ago

    Likely bad rings. Possibly a bad valve, too.

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