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  • 1965 - 1973 Classic Mustangs -General/Talk-
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white smoke in exhaust, not oil or water

  • Thread starter Thread starter VTStang66
  • Start date Start date Jun 9, 2008

VTStang66

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Apr 2, 2001
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Rockwall, TX
Jun 9, 2008
#1
  • Jun 9, 2008
  • #1
I got this 331 running a couple days ago and the exhaust smokes white a little. Both tailpipes, but I have an x-pipe so that probably doesn't mean much. I figure it's not water or oil because I don't smell antifreeze or burning oil, and it's definitely smoke, not vapor. I haven't driven the car other than a mile up the road to seat the rings, but I have done the cam breakin procedure twice (once with single and once with double springs), and idled it long enough to set the lash (mechanical cam). All together it's on its 3rd pan of oil and I think all the breakin stuff has burned out of it by now. It smells rich. What is this white smoke?
 

gtss

Member
Apr 30, 2002
133
2
19
Airdrie,Alberta
Jun 9, 2008
#2
  • Jun 9, 2008
  • #2
is it an auto trans?
leaking modulator valve will allow ATF to be sucked into the intake
just a thought
gtss
 
B

bnickel

Founding Member
Aug 21, 2002
5,640
3
77
lubbock, texas
Jun 9, 2008
#3
  • Jun 9, 2008
  • #3
if it has an auto trans it could be a bad vacuum modulator allowing trans fuild to be sucked up into the intake tract and burned in the exhaust, that's th only other option besides oil or water
 

VTStang66

Founding Member
Apr 2, 2001
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Rockwall, TX
Jun 10, 2008
#4
  • Jun 10, 2008
  • #4
manual trans
 
B

bnickel

Founding Member
Aug 21, 2002
5,640
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77
lubbock, texas
Jun 10, 2008
#5
  • Jun 10, 2008
  • #5
wow, both of us said the same thing about the same time, i guess i was typing my reply as he was sending his. 3

anyway, it' back to the engine for this one. my guess is that if it's a new motor the rings haven't fulley seated yet and you'll have a little smoke until the rings are fully seated, mine was the same way until the rings seated
 

gtss

Member
Apr 30, 2002
133
2
19
Airdrie,Alberta
Jun 10, 2008
#6
  • Jun 10, 2008
  • #6
OK so my timing is off for this reply

but I agree, perhaps pull the PCV valve with the engine running to see how much smoke is coming from the crankcase,
if it appears to be alot, then the rings need some more break in

gtss
 

Fast63

New Member
Sep 20, 2007
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Jun 11, 2008
#7
  • Jun 11, 2008
  • #7
VTStang66 said:
It smells rich. What is this white smoke?
Click to expand...

You're running rich. You need to tune your carb a little leaner. But before you do, pull the spark plugs out and post a pic if you can. Black plugs = no good. White plugs = no good. A lot of junk on everything = no good. Ideal conditions are a nice tan burn or a dark tint. No gunk.

So let us know what you see.
 

garystocker

Member
Jan 2, 2005
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New Jersey
Jun 12, 2008
#8
  • Jun 12, 2008
  • #8
White smoke is always caused by water. It doesn't take much, and you won't smell it.

Has the coolant level remained constant?

Ansy sign of water on the oil dipstick after being left overnight?
 

Fast63

New Member
Sep 20, 2007
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0
Jun 12, 2008
#9
  • Jun 12, 2008
  • #9
garystocker said:
White smoke is always caused by water. It doesn't take much, and you won't smell it.

Has the coolant level remained constant?

Ansy sign of water on the oil dipstick after being left overnight?
Click to expand...

White smoke can mean other things than coolant. He also stated the smoke smells, which would mean it's not coolant.

Looking at the spark plugs can also help determine if it's coolant, oil, or excessive fuel. So I would go ahead with doing that.
 

garystocker

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Jan 2, 2005
305
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New Jersey
Jun 12, 2008
#10
  • Jun 12, 2008
  • #10
Yes I should have said that it is most likely water causing the white smoke. Rule that out before looking for trouble you don't have.

Smoke smells are going to be there with or without water present, and since they are present with the vapor, you consequently can see vapor in with the smoke, and you smell only the smoke. Especially if it is a slight amount of water.

How much white smoke is there? Slight is normal.

Do you see evidence of white liquid on the dipstick and is the coolant level constant? If you don't have enough run-time to make these determinations, run it and wait until you do.

Good Luck.

Tell us what you find.
 

VTStang66

Founding Member
Apr 2, 2001
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Rockwall, TX
Jun 13, 2008
#11
  • Jun 13, 2008
  • #11
I think whoever said it was the rings was right. I took it out again yesterday and got them seated a little better and the smoke went away. I'm waiting on a balancer spacer so I can put the right balancer on it before I really go out and romp on it, but so far everthing looks great. I took a video:

http://www.youtube.com/watch?v=glxW9PI2PUA

Thanks for the replies!
 

Pakrat

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Aug 6, 2000
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Currently: NH Originally: Rhode Island (and all po
Jun 13, 2008
#12
  • Jun 13, 2008
  • #12
The problem could be water or you need to seat the rings better. (J/K)

I just wanted to pop in and say hey buddy! So how's life been? Still bald?
 
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