hi guys
So my f250 has been in the garage for a few months while i was working on it and since then its developed a pretty serious smoke issue out of the exhaust. I put some new valve cover gaskets (which means i had to also pull many components including the upper intake plenum). I replaced the gaskets and put everything back together. The only thing that i haven't replaced yet are the small colored vacuum hoses. I was wondering if the vacuum hoses would cause the smoke or not. When i parked it it smoked a little, no more than normal for a truck with 211000 miles. But i started it for the first time to service the power steering and about a minute after it started smoking like a freight train. I would like to figure this out soon. It runs and sounds great and isnt loosing oil. Thanks in advance

 

My guess would be valve seals are bad dried up from setting or possibly rings .Idrive it see if it clears up.If not install a new set of valve seals.

 

What color smoke? White, blue, black? Is the truck low on coolant at all? Does the smoke smell sweet like coolant, oily, like fuel, or eye burning like a top end cleaner?

 

I too was thinking valve guide seals. Driving it daily keep them swelled and lubricated. Now after sitting for extended amount of time, they have shrunk, and perhaps have many small breaks/cracks around the sealing area of the valve stem allowing oil into the combustion chamber.

 

Depending on the year of truck, the broken vacuum lines will either cause a minor or severe lean condition. I don't think this would cause smoke. Blue smoke is oil burning. Sweet smell is coolant.

 

Its white smoke. The coolant has run low since i got it but it was do to a leaky radiator hose (thus far in the trouble shooting process). I was just thinking about the fuel/air ratio with disconnected lines. It would make since as the smoke picks up when the truck slows to normal idle speed (generally starts and runs around 1500rpm for a minute and then slows) im really hoping this is it. Do the lines on the tree on the intake control the opening/closing of the baffles in the intake? Its a 1991 by the way. A little history ive owned the truck since mid december and i drove it about 2 hours home and since then it's sat while ive been getting it ready for inspection/daily use. The owner before me didnt really put many miles on it lately because he only used it as an off road/mud truck so it's accustom to sitting. Sadly that also led to some neglect in maintanence. I did start it once a week for a few minutes to circulate everything for a few weeks till it was in the garage. When i drove it home it didn't smoke much at all as well as the weekly starts. But now its bad. So hopefully its the lines. I'm going to check the oil for coolant tomorrow.

 

White Smoke is water and antifreeze ;possibly leaking head gasket cracked head .Meaning your getting water in combustion chamber from cooling system .

 

What do you mean by 'baffles on the intake'? The vacuum lines are to supply vacuum to items like the FPR, brake booster, some sensors, etc. It's more of an output item in that there is nothing inside the intake that uses vacuum. Everything that needs the vacuum pressure is outside of the intake.

 

Head gasket, intake gasket, or a cracked head. Is there coolant in the oil?

 

My f150 recently Did that u said it was sitting for a while. Like possibly over winter; you might have got a little condensation in the gas I put some seafoam and fresh gas drove it for like 10 mins and my smoke went away

 

You only get the sweet smell if there is coolant in the radiator... if someone just filled it with water then all you get is white non-smelly steam.

Pull all the plugs and eyeball them... great way to see what's going on in each cylinder.

 

Will definitely check out the plugs. It could be the condensation though. It sat pretty much empty for a while since i got it and had about a gallon before that. Maybe some moisture got in it. I will start it and check again. Thinking back the smoke was pretty light in color but it smelled the same as the smoke from under the hood (from oil that had leaked onto the exhaust manifold). All of the coolant that i have ever put in it is anti freeze. i haven't put any water in it do to the cold weather and in the tester it is definatly mostly anti-freeze. I did the oil drop in the glass of water test and it seemed to check out good as far as i could tell. The drop of oil kept its consistency and didn't disperse. I'm going to try the sea foam, the vacuum lines and give it a few miles down the road and see if it helps. The oil looks and smells clean to.

 

Well i put the sea foam in it yesterday and let it sit for a few minutes. The smoke went down at least 3/4. I went out and let it run today and there wasnt much smoke at all so hope fully this will remedy the problem. Thanks alot for the help and i'll get back on if anything comes up