{What he said...} 
White exhaust smoke
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White exhaust smoke
My 69/350 runs great, but when it gets up to opperating temp the right hand side exhaust only has white smoke come out. It isn't too thick, but noticeable. It doesn't smell like oil or gas smoke so that leads me to believe it is water. Does this sound like a bad intake manifold gasket or something else?
Racer
Joined: Mar 2008
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Bad gasket or it could be a cracked cylinder head. If your running with a coolant mix, the smell should be pretty distinct. Burning antifreeze has it's own smell as opposed to oil. Is your coolant radiator level going down? Can you do a coolant system pressure check to confirm a leak?
Pro
Joined: Feb 2009
Posts: 589
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From: PA
Check the right side intake manifold bolts. 1 or some of them may have come loose causing coolant to be sucked in the cylinder. If so, take 1 out at a time, clean the bolt threads, add a little Permatex 2 to the threads and put it back in.
This is probably all it is.
This is probably all it is.
Racer
Joined: Mar 2008
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Hoping is good. But, as we know, water doesn't compress well and has a bad tendency to modify piston tops with holes. So, I hope he finds out what's going on real soon.
Pro
Joined: Feb 2009
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From: PA
From what he said, it's taking a long time (reaching a certain engine temperature) and then he's seeing steam coming out of the exhaust, and not that much.
A blown head gasket, there would be steam billowing out of the exhaust, right at at start up. I'll say again (for his sake) lets hope it's an intake to head gasket. It may have a tiny coolant leak being sucked in by 1 of the cylinders.
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Pro
Joined: Jun 2009
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From: Fleetwood PA
Does it ever stop smoking? If you drive it infrequently water can condinsate in the muffler, and not be vaporized till the exhaust gets hot all the way back to the muffler.(that can take a while) I know I have this problem from time to time with my sidepipes, and assume it could happen with standard exhaust as well. Like others have said, antifreeze smoke is different,and would have a kind of sweet smell. Hold you hand over the pipe for a little bit, and see if it's just water, or if it leaves a slick residue like antifreeze.
Safety Car
Joined: Apr 2000
Posts: 3,802
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From: Wichita KS
My 69/350 runs great, but when it gets up to opperating temp the right hand side exhaust only has white smoke come out. It isn't too thick, but noticeable. It doesn't smell like oil or gas smoke so that leads me to believe it is water. Does this sound like a bad intake manifold gasket or something else?
If you don't keep your coolant changed it can become acetic and eat at the aluminum.
I had to replace an intake manifold on an '85 LB9 because of that. Had the same symptoms as you.
Another thing to look for is bubbles in the coolant if there is a crack in the head or a void in the intake gasket anywhere near an exhaust port.
cc
Instructor
Joined: Sep 2006
Posts: 175
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From: Omaha ne
Does it ever stop smoking? If you drive it infrequently water can condinsate in the muffler, and not be vaporized till the exhaust gets hot all the way back to the muffler.(that can take a while) I know I have this problem from time to time with my sidepipes, and assume it could happen with standard exhaust as well. Like others have said, antifreeze smoke is different,and would have a kind of sweet smell. Hold you hand over the pipe for a little bit, and see if it's just water, or if it leaves a slick residue like antifreeze.
Pro
Joined: Feb 2009
Posts: 589
Likes: 1
From: PA
Does your 350 have an aluminum intake with iron heads? If so, there's the possibility the intake has corroded and pitted near one of the water jackets.
If you don't keep your coolant changed it can become acetic and eat at the aluminum.
I had to replace an intake manifold on an '85 LB9 because of that. Had the same symptoms as you.
Another thing to look for is bubbles in the coolant if there is a crack in the head or a void in the intake gasket anywhere near an exhaust port.
cc
If you don't keep your coolant changed it can become acetic and eat at the aluminum.
I had to replace an intake manifold on an '85 LB9 because of that. Had the same symptoms as you.
Another thing to look for is bubbles in the coolant if there is a crack in the head or a void in the intake gasket anywhere near an exhaust port.
cc
Lots of details he left out.
We may never know the outcome of this one. He's not coming back to talk to us.
Last edited by 65747785; Oct 27, 2009 at 09:20 AM.
Racer
Joined: Oct 2009
Posts: 441
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From: San Antonio TX
This has worked for me ..but I'm wierd .....
get a plug to pressurize the exhaust pipe end with shop air..look for bubbles in the radiator or listen for air by passing in the block ? I found a bad head gasket by doing this before ...
get a plug to pressurize the exhaust pipe end with shop air..look for bubbles in the radiator or listen for air by passing in the block ? I found a bad head gasket by doing this before ...
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Thanks for all the advice. Here is some of the info I left out.
The heads are cast iron. The motor was "rebuilt" before I bought it a few months ago. I don't know the extent of the rebuild. I tightned the intake manifold before the first time I fired it. After running it a couple of times, I noticed there was water in the oil. I checked the intake bolts and they were as loose as could be. I tightned them again and changed the oil and now it does what I described in the first post.
I think that's about all I know. It does blow a lot of water out the exhaust, but if it was pooling in the exhaust and then vaporizing, wouldn't it smoke out of both sides?
Oh yea. I checked the head bolts today, and they were all tightned to spec.
The heads are cast iron. The motor was "rebuilt" before I bought it a few months ago. I don't know the extent of the rebuild. I tightned the intake manifold before the first time I fired it. After running it a couple of times, I noticed there was water in the oil. I checked the intake bolts and they were as loose as could be. I tightned them again and changed the oil and now it does what I described in the first post.
I think that's about all I know. It does blow a lot of water out the exhaust, but if it was pooling in the exhaust and then vaporizing, wouldn't it smoke out of both sides?
Oh yea. I checked the head bolts today, and they were all tightned to spec.
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Are you continually loosing coolant?
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It does look like the coolant level is low. I'll probly pick up an intake manifold gasket and change it. It looks easy to do. Do I need to put permatex on the threads of the bolts or should I use loctite threadlocker?