Smoke : Valve seal or piston ring - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

F3600 · 02-20-2003, 12:16 PM

Hi !
3 month ago my car started to burn a lot of oil .. Well

at idle may car is smoking a litlle

After a 3-4 second load at 4000 RPM when i release the throttle there a very big cloud
of smoke coming out my exhaust.

anyway ive got a compression test and the mechanic was telling me it was one off my piston ring... i have read some webpage and its look like more a valve seals problem but i want your opinions just to be sure.

if i take out my valve cover, can i see the valve seal and see if they need repair ?

one more thing .. i opened my oil feed on the valve cover and it was blowing oil everywhere and there was some Puff of smoke coming out at intermitent interval.

well hope you can help me.. if i cannot do nothing im gonna buy an old ka24E. I want to keep my 240sx its a damn nice car...

cya everyone
thx for the help !

Fred

*Jeff240sx* · 02-20-2003, 01:53 PM

Does the car smoke when you start it, or accelerate from a stop light, or when you punch it?
If it smokes after sitting, it's probably a valve seal.. if it smokes when you shift or punch it, it's probably a piston ring.
-Jeff

F3600 · 02-20-2003, 02:09 PM

when i start my car it doesnt smoke .. the smoke start after maybe 30 sec but when my car is at normal temp there a lot more smoke

when im driving i have a long smoke cloud that follow me and when i stop.. theres a burst of smoke coming out almost 2x the size of my car ...

pretty chezzy feeling when everybody look at you

(i dont drive my car anymore for that reason)

Fred

*AceInHole* · 02-20-2003, 04:35 PM

What were the #'s from the compression test? If the mech said it was a piston ring from the compression test, then I'm guessing you're numbers were off. If it was a valve seal, your compression numbers would be fine (unless you ALSO had a bad valve seat). In fact, oil leaking into the combustion chamber from a bad valve seal might raise your compression test numbers. IMO it's something below the head (assuming the compression test showed a failing number on it) like a headgasket or piston ring.

F3600 · 02-20-2003, 06:47 PM

There were one cylinder i think were very low (it was 3-4 month ago i dont remember...) well im guessing an engine swap would be more simple . after the swap im gonna tear apart the old one to actually check what wrong with it and learn :P

Thx for you help

02-20-2003, 12:16 PM	#1
F3600 Zilvia Junkie Join Date: Apr 2002 Posts: 364 Trader Rating: (0) Feedback Score: 0 reviews	Smoke : Valve seal or piston ring Hi ! 3 month ago my car started to burn a lot of oil .. Well at idle may car is smoking a litlle After a 3-4 second load at 4000 RPM when i release the throttle there a very big cloud of smoke coming out my exhaust. anyway ive got a compression test and the mechanic was telling me it was one off my piston ring... i have read some webpage and its look like more a valve seals problem but i want your opinions just to be sure. if i take out my valve cover, can i see the valve seal and see if they need repair ? one more thing .. i opened my oil feed on the valve cover and it was blowing oil everywhere and there was some Puff of smoke coming out at intermitent interval. well hope you can help me.. if i cannot do nothing im gonna buy an old ka24E. I want to keep my 240sx its a damn nice car... cya everyone thx for the help ! Fred

02-20-2003, 01:53 PM	#2
Jeff240sx I hate you too... Join Date: Jul 2001 Location: Tampa, FL Age: 42 Posts: 5,828 Trader Rating: (0) Rides Gallery: Jeff240sx Feedback Score: 0 reviews	Does the car smoke when you start it, or accelerate from a stop light, or when you punch it? If it smokes after sitting, it's probably a valve seal.. if it smokes when you shift or punch it, it's probably a piston ring. -Jeff __________________ Whatup?

02-20-2003, 04:35 PM	#4
AceInHole Autox Technician Join Date: Dec 2001 Location: New Haven, CT Age: 44 Posts: 3,961 Trader Rating: (0) Rides Gallery: AceInHole Feedback Score: 0 reviews	What were the #'s from the compression test? If the mech said it was a piston ring from the compression test, then I'm guessing you're numbers were off. If it was a valve seal, your compression numbers would be fine (unless you ALSO had a bad valve seat). In fact, oil leaking into the combustion chamber from a bad valve seal might raise your compression test numbers. IMO it's something below the head (assuming the compression test showed a failing number on it) like a headgasket or piston ring. __________________

02-20-2003, 02:09 PM	#3
F3600 Zilvia Junkie Join Date: Apr 2002 Posts: 364 Trader Rating: (0) Feedback Score: 0 reviews	when i start my car it doesnt smoke .. the smoke start after maybe 30 sec but when my car is at normal temp there a lot more smoke when im driving i have a long smoke cloud that follow me and when i stop.. theres a burst of smoke coming out almost 2x the size of my car ... pretty chezzy feeling when everybody look at you (i dont drive my car anymore for that reason) Fred

02-20-2003, 06:47 PM	#5
F3600 Zilvia Junkie Join Date: Apr 2002 Posts: 364 Trader Rating: (0) Feedback Score: 0 reviews	There were one cylinder i think were very low (it was 3-4 month ago i dont remember...) well im guessing an engine swap would be more simple . after the swap im gonna tear apart the old one to actually check what wrong with it and learn :P Thx for you help