Smoke troubleshooting

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Wazzabie

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Does this look like blue or white smoke?

The engine has sat for 15+ years with only an occasional engine startup for about 1-2 minutes over the 15 years. I rebuilt the carburetor, installed new fuel lines and a gas tank. The smoke is at startup and continues at idle after the engine is warm. I recently have put about 3 miles on the vehicle and it still smokes. This is a 78 350v8- TH350.

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GTX63

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It looks white but pictures aren't always as good as being there. It is common to see white smoke from condensation from a cold start, especially in cool temps.
How is the engine running?
Is the temp gauge showing that the engine is running hot?
Is the oil discolored?
Stick your head in the smoke and smell it.
When an old truck sits for 15 years with only a start up every long once in a while, rings stick, valve seals rot, head gaskets deteriorate; in other words, the truck needs to be driven.
I have had engines that smoked like a wet leaf fire completely wake up after a few weeks of regular use. In your case, we probably need a little more information.
 

Rickf

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I vote for one of three things; valve guides, head gaskets, or rings in no particular order. If the smoke lessens, valve guides. If the smoke smell "sweet" or bubbles in the radiator, head gaskets.
 

Ricko1966

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Drive it for a couple of weeks. Does it use oil? Does it get hot? Does it have any symptoms? There could be rings stuck,rats nests,condensation etc. In the exhaust,dried up valve seals,a lot of this might just improve with a few miles. You've only put 3 miles on it in 15 years,give bit a little time to scuff the surface rust off the cylinders etc.etc.
 

DoubleDingo

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Looks more like steam to me. All vehicles do that when they're cold and it's cool outside. Does it do it all the time, or just when it's cold outside? 3 miles of driving may not be enough to get it hot enough to stop the steam/condensation. Aside from it being possible steam, the others have good suggestions.
 

squaredeal91

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Looks like cold air steam in pictures. Sitting engines need to be driven to re-seat things. Usually sitters run better the more you drive them And CHANGE the OIL and filter if haven't done so already. Just drive it.
 

85K304SPD

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Valve stem seals, maybe valve guides too.
 

Ricko1966

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vacuum modulator?
This is a real good possibility on something sitting this long,and easy to check. Pull the vacuum hose at the vacuum modulator. Is there any transmission fluid in it?
 

Wazzabie

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Drive it for a couple of weeks. Does it use oil? Does it get hot? Does it have any symptoms? There could be rings stuck,rats nests,condensation etc. In the exhaust,dried up valve seals,a lot of this might just improve with a few miles. You've only put 3 miles on it in 15 years,give bit a little time to scuff the surface rust off the cylinders etc.etc.
It is not using oil. I put in fresh motor oil and there is no milky color in the oil. The motor oil is new old stock from the mid 90s however. That might be a good thing since back then the motor oil had more zinc. The engine has not overheated.
 

85 Squarebody76

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Does this look like blue or white smoke?

The engine has sat for 15+ years with only an occasional engine startup for about 1-2 minutes over the 15 years. I rebuilt the carburetor, installed new fuel lines and a gas tank. The smoke is at startup and continues at idle after the engine is warm. I recently have put about 3 miles on the vehicle and it still smokes. This is a 78 350v8- TH350.

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If the smoke is pure white after motor running for 10 plus minutes then the trans vac modulator is bad. When the diaphragm goes bad the motor sucks the fluid up and into the motor and burns it .. hence the chalk white smoke. It will smoke as long as the motor is running.. Check the trans fluid...
 

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