I have a thought about new engine smoking.

[#1 Ford Fan]

Hello, I have posted a couple times about my 2002 4.0l engine blowing smoke. I have a new theory and wanted some input on it if possible. As I have said, the engine smokes after it warms up a bit and I have checked everything I can think of why its doing this. By the way, the smoke is more white than blue so I think its coolant? The original engine had a broken valve spring and blown head gasket and was neglected by the guy I bought it from. My theory/question is, could the exhaust be full or have some coolant and oil in it and is burning off as it warms up? I'm grasping I know but I just cant think of anything else that would cause this. I have checked vacuum lines, coolant lines, compression checks and nothing. The engine runs great but smokes. Any ideas would be great. Thanks.

 

[rusty ol ranger]

Hello, I have posted a couple times about my 2002 4.0l engine blowing smoke. I have a new theory and wanted some input on it if possible. As I have said, the engine smokes after it warms up a bit and I have checked everything I can think of why its doing this. By the way, the smoke is more white than blue so I think its coolant? The original engine had a broken valve spring and blown head gasket and was neglected by the guy I bought it from. My theory/question is, could the exhaust be full or have some coolant and oil in it and is burning off as it warms up? I'm grasping I know but I just cant think of anything else that would cause this. I have checked vacuum lines, coolant lines, compression checks and nothing. The engine runs great but smokes. Any ideas would be great. Thanks.

Thats very possible. But it should clear up after a few dozen miles

 

[Uncle Gump]

One good 20 mile trip at highway speed should clear the exhaust up if that's what the problem is.

 

[RonD]

Coolant evaporates/boils at 235degF in an exhaust system
Exhaust runs at 750-900degF
So as said above, that ship has sailed if you have run the engine longer than 10min

Does it lose coolant?
If so..............


Simple test for oil burning is a hill and a rear view mirror
Warmed up engine
Drive to the top of the hill and go down the other side using the engine to slow you instead of brakes, i.e. shift to a lower gear
This increases the vacuum in the intake above 25-30"
After 30-60seconds shift to Neutral and REV the engine a few times and watch for exhaust smoke in rear view mirror
If you see blue smoke then valve guide seals are leaking, maybe rings, but usually valve guide seals

 

[rusty ol ranger]

Coolant evaporates/boils at 235degF in an exhaust system
Exhaust runs at 750-900degF
So as said above, that ship has sailed if you have run the engine longer than 10min

Does it lose coolant?
If so..............


Simple test for oil burning is a hill and a rear view mirror
Warmed up engine
Drive to the top of the hill and go down the other side using the engine to slow you instead of brakes, i.e. shift to a lower gear
This increases the vacuum in the intake above 25-30"
After 30-60seconds shift to Neutral and REV the engine a few times and watch for exhaust smoke in rear view mirror
If you see blue smoke then valve guide seals are leaking, maybe rings, but usually valve guide seals

Valve guides usually smoke at startup.

 

[RonD]

Valve guides usually smoke at startup.

Yes, but so does exhaust in general if exhaust is cold and outside temp is lower than 60degF

 

[#1 Ford Fan]

Thanks guys, those are some good tips that I will try. I haven't driven it more than a block (too embarrassed) so I will get it out there and drive it for a bit. It hasn't lost any coolant that I can tell so we will see. I know its not rings or seals because its a new engine. Thanks for the tips Guys and I will let you know what happens.

 

[gaz]

@#1 Ford Fan ,
Did you assemble either the short block or the long block?

 

[rusty ol ranger]

Yes, but so does exhaust in general if exhaust is cold and outside temp is lower than 60degF

Wouldnt be blue smoke though lol

 

[#1 Ford Fan]

Well my theory was correct! I drove it for about 3 or 4 miles and it smoked like hell but after about 5 miles it slowly stopped. Now it doesn't smoke at all! Yessss! The exhaust must have been filed with coolant and oil from the original engine when it went bad? So now I can move on to the next stage of my project, suspension. Im going to start by just cranking the torsion bars up some to get clearance for my new 18" wheels with 32's. Then paint which I already have (vermillian red). I bought one of those inflatable spray booths (18'x38') and I cant wait to try it out. Anyway, thanks for all your comments and advice here at TRS. I appreciate it very much. Till next time.