White Smoke At Startup

[JohnV8r]

Hey guys,

I'm splitting the "white smoke" issue off of the Ethanol thread so it doesn't end up "thread-jacked."

As I mentioned, I've been having an unusual amount of white smoke coming out of my starboard 454's exhaust at start up. It sort of bellows an unusual amount of white smoke at start up. Once the engine is warmed up and "goosed" a couple of times, it seems to blow it out. However, this engine seems to emit just a little more "steam" at cruise than my port engine.

Both engines run fine.

I replaced the gasket between the intake manifold and the engine on the starboard engine just last summer.

There is no antifreeze in my oil or transmission fluid...both look new.

Engine temperatures on both engines run where they always have (Port runs just over 160 degrees; starboard runs about 180)

My antifreeze does need to be "topped off" from time to time, but I've always just attributed this to 'overflow' into the coolant recollection system. I've never opened up the cap to find a startling loss of antifreeze.

I found this from a google search on 'white smoke in exhaust':

"If the exhaust billows white smoke for a few seconds when first starting the engine after it has been sitting for a while, such as overnight, and then runs normally, it could mean that the rubber valve stem seals have perished - especially if the vehicle is a few years old and has done over 60/70,000 miles.

Another clue is: does the exhaust smoke smell like fresh, rather than burnt oil."

My exhaust does smell fresh with no hint of oil whatsoever.

I'll try to get pictures up sometime in the next week. Any thoughts?

Thanks in advance.

JohnV8r

[Rawleigh]

John: Have someone else start it and smell the smoke. You will know if it is oil smoke. The valve seals ae why I asked you if it was bluish smoke. It will look whitish as well, but will smell of oil.

[In Memory Walter K]

If it's valve seals, you'll have an oil consumption increase, too. Walter

[Rawleigh]

John: I assume they are freshwater cooled. Get a radiator pressure tester and pressure test the cooling system. that is the best way to mark that off the list. Rawleigh

[jrwolfe]

I had a Tiara with twin 454 Crusaders. When I bought it used, I had a trail of white smoke coming from the port engine. The temp was normal as was the way it ran. I ended up changing the exhaust risers and that eliminated the smoke ( I think steam). For what its worth .....

[PaulJ]

John,

You indicate that more "steam" is seen in stbd after warm-up and initial white smoke blow-out. In your initial post you said...."Engine temperatures on both engines run where they always have (Port runs just over 160 degrees; starboard runs about 180)"

1. Higher temp would mean more steam after warm up. Recco you investigate why stbd runs 20 deg higher than port????
a. clogged risers?
b. heat exchanger going bad/clogged?
c. raw water pump?
d. clogged intake port?
A small amount of reduction in raw water flow will drastically (20 deg) change the temp.

2. Pull plugs on stbd motor. Check them for unusual discolorations, burns, deposits... this might point to source of smoke at startup.

3. If you have a small crack in the head, intake manifold or leak in the gaskets, water in the exahust at start-up could be there and then after heating, expansion takes place to close the gap. You indicated that you replaced the intake manifold gasket.

For what its worth, I only know of white smoke at startup from:
1. Water
2. Carb cleaner
3. Too much fuel additives

After these items burn off.... then clear exhaust, except for steam once at temp.

[Doug Crowther]

guessing you have a coolant weep. When you turn off a hot engine the temp actually rises and the system pressure with it. Sounds like you have a gasket somewhere that is allowing antifreeze into the system. I would suspect an intake or head gasket or exhaust manifold, based on my experiences. As sugested smell the exhaust- does it smell sweet like antifreeze ? A minute amount of antifreeze will make a large amount of white smoke.