If the engine was not warmed up, the rings wouldn't be seated fully, so the oil would help. If that was a cold test, try another one hot. Honestly though, even if the engine was warm, with the consistency of the results I would think that the rings haven't seated yet, rather than being worn or anything. It's possible that whoever built your engine didn't use the right grit hone for the rings you chose to run...
Happens to the best of us... I think that's why we all insist on doing so much of the work ourselves. If you want something done right....
That dosen't seem terrible to me. Looking at my compression gauge booklet, it says you want the lowest reading no worse than 75% of the highest (though on a new engine it should be even) - you're 5% off. Overall readings seem very good to me. My truck looked like someone poured a quart of oil on the valve cover from blowby. I got 120 psi across the board when 175 was normal. Chris
[ QUOTE ] Are you bragging or complaining? [/ QUOTE ] To follow up on what DrJ said, sounds like you're just trying to do something you haven't done before. Obviously there's nothing wrong with your rings, the readings you have reported are exceptional. The question that remains is, "Why did you run a compression test in the first place?". If you're just experimenting then I would suggest that you go to the manufacturers specs to see what the "actual" readings should be. I find it hard to believe that an engine with these readings would be running poorly, at least not because of a loss of compression.
Man, that sounds like great compression. Dose your valve covers have a baffle on the inside under where the PCV valve goes? If not, your PCV valve may be sucking up oil splashing around on your rocker arms. It's possible. Billy
Charlie and Shoebox are right.My smallblock did the same with the plugs.I replaced the intake gaskets they were leaking at the bottom of the intake port and sucking oil in. After new gaskets no more oil soaked plugs.---FEDER
You will almost always get higher pressures after adding oil to the cylinders. This only indicates a bad ring seal when your initial numbers are low. The first place I would look is your PCV valve. If you do not have a good baffle under it, it will suck the oil right out of your engine. I just experienced this for the second time recently. You may want to run your PCV line to the breather instead of the manifold as well. Do you have a vented breather on the opposite vlave cover from the one with the PCV valve? Justice
The best way to see where you stand is to do a leak down test. However, if you are getting numbers near 200 on your compression check, I would think your rings are fine. Check that PCV valve! I am telling you it works like a vacuum hose if you do not have an effective baffle in front of it. The intake gasket is a possibility, but I would eliminate the easy fix first. Feel free to Email me. I will be glad to share more info and pic's with you on this subject. Justice
Let us know what you figure out. Most auto parts stores sell external OEM baffles. There is one that looks like a little square plastic box with a nipple on top and bottom. It plugs in and pushes down flush to your valve cover with a large 5/8 (app.) nipple on the top for your PCV hose. This one works well with a pcv to breather style set up. It is has a baffle and is foam filled. Justice
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