You don't need to be at operating temp to do a compression check. If the engine is out, start it up on the floor for about 10 or 15 seconds to get everything moving again if it's not been run for a while. Then the compression test will be more accurate.
Ok, will do. What do you guys think are good numbers? 150 psi or so, and within 10% of each other? Sorry, I forget. I've spent 6 months in the restoration forum talking about wood, resin, fiberglass, and upholstery. Got to brush back up on the engine stuff.
Depends what engine model. Generally anything over a 100psi. Should tell you in the specs page of the manual to be exact. Make sure you do it with throttle plates at wide open. While you're at it do a cylinder leak down test. It will tell you way more than a compression test alone.
Duh! I guess the engine model would be helpful when trying to get advice huh. It's an '84 Merc 228hp 5.0. If you say it's in the manual, then that'll be easy enough to look up. Mainly, I just didn't know if these tests were even worth doing if I can't run the engine first. Just kinda have the thing sitting on a pallet on the floor.
