2001 GTX RFI compression question

[rkkoeb]

So I just picked up two extremely nice 2001 GTX that I am going to fix/clean up and eventually flip. One the first machine I did a compression test and the once cylinder is dead on 150 PSI. When I did the second cylinder it is showing around 200 PSI and I ran the test several times. What is causing this one side to be such high compression? The machine does run.

 

[burtshaver2021]

Excessive oil from leaking inner seal maybe. Take it on a good run and test again

 

[burtshaver2021]

Or worse, oil from fogging spray making both readings higher, I’ve seen that before

 

[Grim]

With Burt's idea you could take the plugs out ,ground the wires and turn it over a couple times to see if any oil/junk comes out. if so , do it a few times to clear it out and then repeat the test.

 

[rkkoeb]

I am going to try running it for little while on the trailer using the hose and then test compression again.

 

[burtshaver2021]

No need to hook it up to the hose, the hose is only to back flush the engine and shouldn’t be ran for more than 1 minute on the hose. You can run it out of the water without the hose for 30 seconds or so which should be enough. Just run it for 39 seconds, let it sit for an hour, run it for 39 seconds again, and then check the compression