1990 351 Smoke on start up

Hemlock · Sep 18, 2009

I have a 1990 w/a 351. When I start it up it blows white smoke from tailpipe. Not just a little a bunch. After driving a few miles it stops. If I drive everyday and often it does not do it as much. It is when it sits for a few days that it really starts to smoke. I looked under and have no drips or leaks. There is a bit of seapage fron the top end but I have been told that is just a gasket fix. What do you think?

Krafty · Sep 18, 2009

could be a leaky valve seal, on my 429 that had been sitting, after I put it in and started driving it, it would smoke alot at the start but easy up , but still not really stop. when I pulled my springs off I only had 2 out of 16 seals that were not completely destroyed, sounds like you might have one or two starting to leak.

muddrivermike · Sep 18, 2009

That sure sounds like valve seals as Krafty said.Pull your plugs and see what color they are.see if they have indications from oil on them.Now I was told if you use full synethic oil even though you may be burning it,,You wont see anything out of the exhaust.But it isnt as simple as drain and refill it and thats it.You have to do it a couple times to get the old oil flushed out of the engine from the new oil,then when its all synethic it should work...I cant confirm this though.And its defenitly not a fix.

BroncoJoe19 · Sep 20, 2009

White smoke is steam.

Condensation due to changes in temperature can collect inside the exhaust. You'll notice it more when you have a few days that there is a lot of dew.

Broncobill78 · Sep 21, 2009

As Joe said, white smoke is steam. If it's gone after a few min of driving then it's just condensation in the exhaust & perfectly normal, particularly in cold climates. If it *doesn't* go away then you need to look for the source which is usually a head gasket.

Black smoke is oil or fuel that generally comes from something like worn valve seals, piston rings or a carb that's running rich

Gray smoke is usually transmission fluid coming from something like a blown modulator valve.

BroncoJoe19 · Sep 22, 2009

Gray smoke is usually transmission fluid coming from something like a blown modulator valve.

See that! I learn something every day.

Thanks

/emoticons/[email protected] 2x" width="20" height="20" />

Krafty · Sep 23, 2009

I had grey smoke that was engine oil. not black smoke

Krafty · Sep 23, 2009

also if it is infact steam, then that would mean that you are instantly boiling off coolant from inside your combustion chamber that seeps in from your leaky gasket when sitting.

muddrivermike · Sep 23, 2009

I didnt notice he said white smoke

/emoticons/[email protected] 2x" width="20" height="20" />

50joe · Sep 23, 2009

Saw a cherokee blowing grey smoke once. Turned out it was brake fluid. Seal in the master blew, booster sucked it in, through the check valve, down the hose, into the intake. Only did it when you hit the brakes. Now THAT was a one in a million.....lol.

Broncobill78 · Sep 23, 2009

Krafty said:
I had grey smoke that was engine oil. not black smoke

small amounts of oil usually look black, if it's burning a lot of oil the smoke tends to look more blueish. Old engine oil that has a lot of contaminants & old fuel (usually from worn rings) can do that but they're just guidelines & subject to interpretation

/emoticons/[email protected] 2x" width="20" height="20" />

muddrivermike · Sep 24, 2009

50joe said:
Saw a cherokee blowing grey smoke once. Turned out it was brake fluid. Seal in the master blew, booster sucked it in, through the check valve, down the hose, into the intake. Only did it when you hit the brakes. Now THAT was a one in a million.....lol.

Hey ive seen that before,pretty funny when you dont see any brake fluid leaking,just it disappearing. :lol:

50joe · Sep 25, 2009

I thought she was nuts when she told me why she was bringing it in. Always learnin......

muddrivermike · Sep 25, 2009

50joe said:
I thought she was nuts when she told me why she was bringing it in. Always learnin......

Yeah right just when you think you see it all something new always appears to ***** with your head. @-)

1990 351 Smoke on start up

Hemlock

New member

Krafty

New member

muddrivermike

Active member

BroncoJoe19

Active member

Broncobill78

New member

BroncoJoe19

Active member

Krafty

New member

Krafty

New member

muddrivermike

Active member

50joe

New member

Broncobill78

New member

muddrivermike

Active member

50joe

New member

muddrivermike

Active member

Similar threads

Members online

Latest posts

Forum statistics