my compression results - what to do? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Warwick5s · 06-06-2003, 01:44 PM

due to my KA24E burning oil lately i decided to do a compression check.

every cylinder went up to 50 or so on the first crank, then eventually to 153-155 psi. after adding a little bit of oil to the cylinder the initial crank was around 90 but still went to about 155-158 psi.

my engine has about 103k on it, and like i said before burns oil when i give it a lot of gas (but not when i start it up, only at WOT and high rpms). i don't think that compression is so low as to indicated failing rings (especially seeing as how it's within 4 psi across the board.) but the fact that the initial stroke was so low makes me wonder. leaking valve seals would cause more oil burning at startup than high RPMs. headgasket is possible. what else could be causing the smokescreen?

boosteds14 · 06-06-2003, 04:09 PM

if it was valve seals, it would smoke upon start and would get worse the longer the car sits with the engine off.

definitly rings

Warwick5s · 06-07-2003, 04:03 PM

interestingly enough, i did that engine flush that was posted about here before - with the gunk engine flush and automatic transmission fluid, and it doesn't smoke anymore.

no idea...but i'm not complaining

kandyflip445 · 06-07-2003, 04:26 PM

Hmmmmm....Maybe I should actually try that then...

06-06-2003, 01:44 PM	#1
Warwick5s Zilvia Junkie Join Date: Sep 2002 Location: Madison, WI Age: 43 Posts: 504 Trader Rating: (0) Feedback Score: 0 reviews	my compression results - what to do? due to my KA24E burning oil lately i decided to do a compression check. every cylinder went up to 50 or so on the first crank, then eventually to 153-155 psi. after adding a little bit of oil to the cylinder the initial crank was around 90 but still went to about 155-158 psi. my engine has about 103k on it, and like i said before burns oil when i give it a lot of gas (but not when i start it up, only at WOT and high rpms). i don't think that compression is so low as to indicated failing rings (especially seeing as how it's within 4 psi across the board.) but the fact that the initial stroke was so low makes me wonder. leaking valve seals would cause more oil burning at startup than high RPMs. headgasket is possible. what else could be causing the smokescreen?

06-06-2003, 04:09 PM	#2
boosteds14 Zilvia.net Advertiser Join Date: Jan 2002 Location: CIPmotorsports Age: 43 Posts: 1,612 Trader Rating: (0) Feedback Score: 0 reviews	if it was valve seals, it would smoke upon start and would get worse the longer the car sits with the engine off. definitly rings __________________ 240SXONE www.240SXMOTORING.com --- One Stop Shop for Your Nissan 240sx

06-07-2003, 04:26 PM	#4
kandyflip445 Post Whore! Join Date: Sep 2002 Location: Arden, NC Age: 40 Posts: 4,460 Trader Rating: (1) Rides Gallery: kandyflip445 Feedback Score: 1 reviews	Hmmmmm....Maybe I should actually try that then... __________________ My 240 vBgarage

06-07-2003, 04:03 PM	#3
Warwick5s Zilvia Junkie Join Date: Sep 2002 Location: Madison, WI Age: 43 Posts: 504 Trader Rating: (0) Feedback Score: 0 reviews	interestingly enough, i did that engine flush that was posted about here before - with the gunk engine flush and automatic transmission fluid, and it doesn't smoke anymore. no idea...but i'm not complaining