compression test question
Thread Starter
TECH Junkie
Joined: Nov 2001
Posts: 3,029
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From: Chi-Town
compression test question im gonna do a compression test on the car tonight. should i let it warm up a bit before i do it, or is it fine to do it cold? supposaly the rings dont seal that well until warm <shrug>. or is the difference so small i wouldnt even notice it? if im losing compression, im not even gonna bother changing the valve seals to see where my problem is.
Thread Starter
TECH Junkie
Joined: Nov 2001
Posts: 3,029
Likes: 0
From: Chi-Town
well, it does no good when i forget the keys at home (i go to the parents once a week after work for dinner, oops) i did try to pressurize the cylinder. i realized its gonna be a bitch to try and get that tester on all 8 cylinders and to make the fittings tight. stupid tight engines.
Personally, I like to put a fire cracker in the cylinder, and see if it blows anything up. For example, if the cylinder will withstand an 80g firecracker explosion, you have at least 80psi. If it holds that, progressively use larger explosives, until a 150g firecracker holds, if that works and doesn't blow anything up, you're fine. To answer your question though, it probably doesn't really matter if its hot or cold, but it'll be a heck of alot easier/more comfortable working on a warm/cold engine.
Shawn
Shawn
