Exhaust smoke on startup

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texasmike

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The truck I have sat outside for 13 years before I started the resto work on it over two years ago. It has less than 53k miles on it and I noticed that on cold startup, it blows a lot of smoke out the exhaust that clears up quickly.

Is that something I should be worried about and how much would it cost to fix it? I'm pretty sure it would be too much for me to tackle on my own.
 

Scotty D

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Most likely the valve seals are the culprit. It could come out of it the more you run it. If the smoke goes away after it starts is a good sign
 

austinado16

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Color of the smoke is important. Black smoke is too much fuel. Blue smoke is engine oil being burned. White smoke that goes away quickly is water vapor in the exhaust system. White smoke that hangs out for a while, and smells like maple syrup, is coolant.

Generally, if you're seeing blue smoke at start up, you have valve stem seals that have failed, and are allowing the oil sitting on top of the heads around the rocker arms and valve springs, to leak down the valve stems while the vehicle is parked. You could even have a failed valve stem, or more than one. Usually valve stem seals can be replaced in situ.
 

Rickf

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I vote for valve guides and/or seals.
 

Vbb199

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Valve seals more than likely.
 

AuroraGirl

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Is your timing and fuel air mixture correct?
 

Curt

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Engines do not do well sitting.I would take the carb apart and clean.

Take a look at the plugs and timing as she suggested.Look at vacuum hoses,most likely dry rotted.
 

AuroraGirl

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I only suggest it because I had an engine running super rich, super retarded and I thought it burnt oil profusely.

turned out it doesnt burn hardly any if any at all.
 

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