smokin at idle
Thread Starter
Instructor
Joined: Oct 2008
Posts: 128
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From: dunkirk ny
smokin at idle
i have 89 c4, runs great no smoke on accelration, if i stop with engine running after about 3 minutes it starts to blow smoke out tailpipe, looking for ideas to problem.
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
Well smoking at idle or deceleration = valve seals. That is if its oil smoke.
If its steam then its cracked head or blown head gasket.
Hold you hand at the tail pipe while its smoking. If your hand gets wet its probably steam. If it doesn't its probably smoke.
If its steam then its cracked head or blown head gasket.
Hold you hand at the tail pipe while its smoking. If your hand gets wet its probably steam. If it doesn't its probably smoke.
Thread Starter
Instructor
Joined: Oct 2008
Posts: 128
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From: dunkirk ny
smoking
it dosen,t smoke on start up
Racer
Joined: Dec 2007
Posts: 416
Likes: 3
It's valve seals. Probably guides too.
At low rpm the oil coming out of the pushrods can flood the rocker pivot area then run down the valve spring and get on the valve stem and get sucked in by the high idle vacuum.
At higher rpm the oil splashes around more and doesn't get on the valve stems so much and theres not as much vacuum.
And it might not smoke at start up because theres no oil sitting around the valve seal area. Let it idle for a while before shutting it off, it'll smoke on start up.
At low rpm the oil coming out of the pushrods can flood the rocker pivot area then run down the valve spring and get on the valve stem and get sucked in by the high idle vacuum.
At higher rpm the oil splashes around more and doesn't get on the valve stems so much and theres not as much vacuum.
And it might not smoke at start up because theres no oil sitting around the valve seal area. Let it idle for a while before shutting it off, it'll smoke on start up.
Thread Starter
Instructor
Joined: Oct 2008
Posts: 128
Likes: 0
From: dunkirk ny
smokin
It's valve seals. Probably guides too.
At low rpm the oil coming out of the pushrods can flood the rocker pivot area then run down the valve spring and get on the valve stem and get sucked in by the high idle vacuum.
At higher rpm the oil splashes around more and doesn't get on the valve stems so much and theres not as much vacuum.
And it might not smoke at start up because theres no oil sitting around the valve seal area. Let it idle for a while before shutting it off, it'll smoke on start up.
At low rpm the oil coming out of the pushrods can flood the rocker pivot area then run down the valve spring and get on the valve stem and get sucked in by the high idle vacuum.
At higher rpm the oil splashes around more and doesn't get on the valve stems so much and theres not as much vacuum.
And it might not smoke at start up because theres no oil sitting around the valve seal area. Let it idle for a while before shutting it off, it'll smoke on start up.
