J
Jeff Pearson
Guest
Can anyone tell me what this is, every now and then in the morning on start up, smoke comes from the exhaust, could this be valve stem seals?
JonM
Well-known member
black = excess fuel
white = water or coolant
bluish = oil
white = water or coolant
bluish = oil
jsinga
Well-known member
- Joined
- Nov 23, 2001
- Messages
- 280
- Location
- Savannah, GA, USA
- Corvette
- 87 Silver Coupe Way over 200k miles
More than likely the valve seals are hard as a rock. A small amount of oil runs down the stems overnight. In the morning it is sucked in the cylinder and since all the oil doesn't burn up you get the smoke.
JS
JS
Corvette-Pilot
Well-known member
;stupid
- Thread starter
- #5
V
Vrotate
Guest
Valve stems.... It's a common occurance. I just replaced mine. Easier than you might think! You need an air compressor and a valve compressing lever. Buy a book and give it a shot. Hell, put some roller rockers while your in there!!! Love mine!
Good luck
Vrotate
Good luck
Vrotate
- Thread starter
- #6
L
LPDesRoche
Guest
I concur....valve stem seals...very easy job as stated above. It would be an excellent time to swap to a set of roller rockers while you are in there.
- Thread starter
- #7
S
scorp508
Guest
Valve stem seals!
vigman
Motor head!!!!
- Joined
- Feb 13, 2001
- Messages
- 3,471
- Location
- Valencia, CA,USA
- Corvette
- 88 Convert ( SOLD ) /1973 coupe 4 speed/1964 Vert!
Smell the startup!
If you are behind the car in the morning
( having somebody else start the car)
You can smell ONE problem.....
If it flooded ( due to leaky injectors) it will stink like fuel on start up.
The OIL ( from bad valve stem seals) will not stink like fuel will.
If you suspect coolant... put clean WHITE paper towels down on the ground about 6" away from both tail pipes.... the exhaust will belch out green blobs onto the paper towels.. if it is just condensation.. you will get gray gook on the towels ( from the water washing away the coating internal to the exhaust system)
If you just stick a paper towel into the tail pipe and give it a wipe ( engine off ) you should just have a grey DRY powder which is normal.... if it has any oil on it.. the rings are starting to go...OR you are burning oil somewhere else.
If you watch, look & smell... it will tell you ALOT about the problem!
Vig!
If you are behind the car in the morning
( having somebody else start the car)
You can smell ONE problem.....
If it flooded ( due to leaky injectors) it will stink like fuel on start up.
The OIL ( from bad valve stem seals) will not stink like fuel will.
If you suspect coolant... put clean WHITE paper towels down on the ground about 6" away from both tail pipes.... the exhaust will belch out green blobs onto the paper towels.. if it is just condensation.. you will get gray gook on the towels ( from the water washing away the coating internal to the exhaust system)
If you just stick a paper towel into the tail pipe and give it a wipe ( engine off ) you should just have a grey DRY powder which is normal.... if it has any oil on it.. the rings are starting to go...OR you are burning oil somewhere else.
If you watch, look & smell... it will tell you ALOT about the problem!
Vig!
- Thread starter
- #10
D
DkBG
Guest
BigRed , are you saying that cold start injectors are unessessary ? Not argueing , just asking . Cliff
vigman
Motor head!!!!
- Joined
- Feb 13, 2001
- Messages
- 3,471
- Location
- Valencia, CA,USA
- Corvette
- 88 Convert ( SOLD ) /1973 coupe 4 speed/1964 Vert!
Well cold start in LA is a joke
I mean we MIGHT get down to the low 50's normally.. and ( God Forbid ) It actually snowed here that would make news for a week!
I mean we have "STORM WATCH" when it RAINS!
I have pulled my cold start sensor wire.
Vig!
I mean we MIGHT get down to the low 50's normally.. and ( God Forbid ) It actually snowed here that would make news for a week!
I mean we have "STORM WATCH" when it RAINS!
I have pulled my cold start sensor wire.
Vig!
BigRed
Well-known member
Truly they are not needed. I have started my car well below 32 (Freezing) with NO issues. I think the only difference (and it may be in my head) was an extra 1 or 2 crank from the starter...Minor
Its really not worth getting into a mess over I just disconnected it.
Its kinda like Coolant running through the throttle bodys alot of cars don't have it and do fine and alot have it and do fine as well. Personally I have NEVER heard of a instance where a bypass was done and a problem arose. (And look where I live Heheh)
Its really not worth getting into a mess over I just disconnected it.
Its kinda like Coolant running through the throttle bodys alot of cars don't have it and do fine and alot have it and do fine as well. Personally I have NEVER heard of a instance where a bypass was done and a problem arose. (And look where I live Heheh)
larryfs
Well-known member
how bout when you mash the pedal down, and you see smoke in the rear view mirror?
my first thought was oil, but it doesn't burn any oil at all. and the car was well maintained with pennzoil. (not that that means anything)
next thought was head gasket, but then it would smoke all the time, right??
so now I'm thinking O2 sensor, and it must be black smoke coming out cause it's running rich at WOT? (OBD1 car)
you could only see the smoke in the dark when another cars headlights are behind me illuminating it. In the day time, you see nothing.
how can I figure out why it smokes under full throttle?
thx
my first thought was oil, but it doesn't burn any oil at all. and the car was well maintained with pennzoil. (not that that means anything)
next thought was head gasket, but then it would smoke all the time, right??
so now I'm thinking O2 sensor, and it must be black smoke coming out cause it's running rich at WOT? (OBD1 car)
you could only see the smoke in the dark when another cars headlights are behind me illuminating it. In the day time, you see nothing.
how can I figure out why it smokes under full throttle?
thx
- Thread starter
- #14
D
DkBG
Guest
Does your check engine light ever come on when your driving , then go back out after awhile ? Cliff
larryfs
Well-known member
nope, no check engine light. just the exhaust smoke. it seems rich, not like oil, not like antifreeze.,,,,,
- Thread starter
- #16
V
Vrotate
Guest
full throttle
If no oil lose then don't worry about it. Most cars bellow a little black smoke under full throttle. It's unburnt fuel. This usually only happens under high rpm's.
If no oil lose then don't worry about it. Most cars bellow a little black smoke under full throttle. It's unburnt fuel. This usually only happens under high rpm's.
- Thread starter
- #17
D
DkBG
Guest
I wonder if a different brand of gas might help . Cliff
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