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Leak Down Test

Performed a leak down test on a 3.2
The results are:
cyl 1=40% cyl 2=2% cyl 3=2% cyl 4=30% cyl 5=1% y cyl 6= 3%
Does this engine need to be rebuilt or what should I do to find what is wrong with it.

Old 11-01-2013, 08:28 PM
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You can should get more info from a leakdown test. testing cyl #1 & #4, you should be able to hear where the air is escaping. Intake or exhaust would indicate the respective valve is leaking, if the air is leaking out the vent then it is leaking past the rings.

Has the car been sitting? If so, drive it & test again.
Old 11-02-2013, 03:53 AM
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Did you confirm that the valves were in adjustment before you ran the test? If you did start listening for air leaking past the valves. Also try a small amount of oil in the suspect cylinders (1&4) and see if that improves your numbers. Could be as simple as too tight on your valve lash. Warren
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Old 11-02-2013, 03:53 AM
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Good advice here. Valve adjustment, drive car and repeat test. Also, I would do a compression test. 30 and 40% leak down numbers will likely be confirmed with lower compression.
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Old 11-02-2013, 04:01 AM
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Thanks for the comments.
The engine is out of the car, we tested it before installing it. No work was done to the engine, the transmision had a problem.
The air is leaking from the vent, like dad911 said I suspect the leak is from the rings.
Now, is there another test I can do to make sure what is wrong with the rings ?
The engine has been out of the car for almost 20 months.
Old 11-02-2013, 03:35 PM
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With the engine sitting around for 20 months, stone cold, your leak down test is not that valid. The good numbers are good, and the bad numbers 40% are not reliable. You want to test it hot, with the cylinders wet.

I would say forget about it, drive it, and re-test.

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Old 11-02-2013, 04:03 PM
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