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10 hours ago, bluez said:

Note, battery should be fully charged to allow full cranking. Also, remember motor should be hot, so valve train is seated. Then remove the plugs.

Ok. So i must take the car for a spin and then perform the tes as @Mark Maras described. I also posted a youtube video for reference

 I don't like to compression test a hot engine because I don't like to remove spark plugs from a hot engine. However if the plugs come out easily it's better to test the engine when it's warm.

Video is fine, except for failing to mention engine should be at normal temperature.

A hot engine will give you the most accurate compression readings.
When testing my engine cold, I found low readings around 130, hot engine were around 170. I like these numbers better..

I agree with Mark, I don't like to remove steel spark plugs from an aluminum head when hot. Too much chance for thread damage.

I also agree that a remote starter makes this an easy job. You don't even need to turn the key on and it can all be done without getting into or reaching into the car.

Plugs pulled out before test. Now i will place the dry test results for your kind reference. I will only perform wet test on plug 4

IMG-20230305-WA0022.jpg

Edited by jalexquijano

On 3/2/2023 at 7:54 PM, Mark Maras said:

 Remove the coil wire, remove the spark plug wires and spark plugs, get comfortable in the seat and turn the engine over (wide open throttle) with the starter until you see oil pressure on the gauge. It shouldn't take long. Then proceed with the test.

Dry test results with choke fully open and gas pedal floored:

Cyl 1: 148 psi

Cyl 2: 150 psi

Cyl 3: 146 psi

Cyl 4: 150 psi 

Cyl 5: 150 psi

Cyl 6 : 149 psi

Wet - Cyl 4: 160 psi

 

I think those are decent numbers…Would like to get an opinion from other folks on running the leak down test just.. to confirm the engine status.

Edited by Yarb

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