Compression test experts please comment
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TECH Apprentice
Joined: Dec 2001
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From: CA
Compression test experts please comment I did a compression test and most of the cylinders were between 160-170psi. One was 150psi and another was 140psi. I poured two capful of Mobil 1 10W30 down into the 140psi cylinder and then when I recranked it went up to about 150psi. Does this sound like a bad ring? The cylinders next to the 140psi cylinder had 160-170psi so it shouldn't be a head gasket.
Another thing is I did not start the car for about 16 hours after I did the compression test. When I did start it, smoke immediately began to appear from the cylinder that I poured oil into. I don't know where it was coming from though, somewhere down there. Spark plug hole, perhaps, not sure. It wasn't like it was a wisp of smoke, it was alot of it. It smoked for probably about 5 minutes and then it cleared up. Does that usually happen? Shouldn't the oil have seeped past the oil rings and back into the oil pan if I had a bad oil ring? I do have Ross nitrous pistons with Total Seal rings, assembled by ARE.
Thanks!
Another thing is I did not start the car for about 16 hours after I did the compression test. When I did start it, smoke immediately began to appear from the cylinder that I poured oil into. I don't know where it was coming from though, somewhere down there. Spark plug hole, perhaps, not sure. It wasn't like it was a wisp of smoke, it was alot of it. It smoked for probably about 5 minutes and then it cleared up. Does that usually happen? Shouldn't the oil have seeped past the oil rings and back into the oil pan if I had a bad oil ring? I do have Ross nitrous pistons with Total Seal rings, assembled by ARE.
Thanks!
Thread Starter
TECH Apprentice
Joined: Dec 2001
Posts: 351
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From: CA
Re: Compression test experts please comment </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Fireball:
<strong>not 100% sure of the answer but I do recall that if oil helps then its a leaky ring...
anyways TTT for you <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Yeah, it might be partly ring, not sure. I'm wondering why it didn't go up to 160-170psi if it was a bad ring, but maybe adding oil wouldn't form that great a seal and that's why?
<strong>not 100% sure of the answer but I do recall that if oil helps then its a leaky ring...
anyways TTT for you <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Yeah, it might be partly ring, not sure. I'm wondering why it didn't go up to 160-170psi if it was a bad ring, but maybe adding oil wouldn't form that great a seal and that's why?
Joined: Nov 2001
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From: Cecil County Raceway!!!
Re: Compression test experts please comment not 100% sure of the answer but I do recall that if oil helps then its a leaky ring...
anyways TTT for you <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
anyways TTT for you <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
