Hi everyone. I've been working on swapping a 2004 5.3 into my truck and I am finally at the point where I can power everything up and start to check electrical components. With that, I decided to test the starter, turn the motor over, and do a compression test. This motor supposedly ran well before the previous owner sold it to me, but I never heard it run. It sat for two years before I could get to this point of turning it over and it is still completely stock. The inside of the motor looked great under the oil pan and valve covers. When I crank it, I get 30 psi oil pressure. When doing the compression test I have all spark plugs out, throttle body held open, and PCM keyed power disconnected. My compression results are kind of all over the place, ranging from 60 psi up to 170 psi. On cylinder #2, after squirting oil in the cylinder the compression jumped up to 150 psi.
I'm wondering what you all would do at this point. Do you think this may just be a symptom of the motor sitting for so long? Or is it a sign that the engine needs more attention? I do not have the fuel system figured out yet so I can't fire up the engine. I'm somewhat curious to get the engine started and see if these compression values improve after the motor is fully lubed up again.
