Help Needed blue - then black smoke at start up

[Greg Reed]

2003 F250 Super Duty Power Turbo 6.0, 111,000 miles.

For a few weeks at start up, blue exhaust briefly, this a.m. black briefly, small cloud momentarily. Have been in sub-freezing temperatures, and that is when it startted happening.

Is it the temperature being in the teens at night or is there something else?

 

[01yellerCobra]

Blue smoke is usually oil and black is fuel. Since its just at start up it might be the valve seals. They allow oil to pass until they warm up and expand. As for the black my guess would be a rich mixture to get the engine fired up in the cold weather. Maybe a glow plug isn't working like it should and isn't burning the entire mixture.

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[Greg Reed]

Blue smoke is usually oil and black is fuel. Since its just at start up it might be the valve seals. They allow oil to pass until they warm up and expand. As for the black my guess would be a rich mixture to get the engine fired up in the cold weather. Maybe a glow plug isn't working like it should and isn't burning the entire mixture.

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"Thank you kindly."

 

[snicklas]

How cold?

I have an 03 with 160,000 and when it's below 20F it will let off a blue puff when it starts, and like yesterday when it was 9F it smoked blue for nearly the first minute. These are not block heater starts. It smokes blue because the engine is cold and the fuel does not burn completely. Blue in a diesel can be fuel or oil, but when it is really cold, it is more than likely fuel because there is just not enough heat in the block to support good combustion. Now it if smokes a puff of blue on a warm start, then I would suspect it is oil and may need addressed.

 

[Greg Reed]

How cold?

I have an 03 with 160,000 and when it's below 20F it will let off a blue puff when it starts, and like yesterday when it was 9F it smoked blue for nearly the first minute. These are not block heater starts. It smokes blue because the engine is cold and the fuel does not burn completely. Blue in a diesel can be fuel or oil, but when it is really cold, it is more than likely fuel because there is just not enough heat in the block to support good combustion. Now it if smokes a puff of blue on a warm start, then I would suspect it is oil and may need addressed.

"Thank you kindly. It got warmer here and the blue puff dissipated at start up... You took a load off my mind. Thanks.

 

[snicklas]

No problem. This is the 8th winter I've had mine. Trust me, the first winter, I had plenty of questions.

Now, if I put the key in it and it starts and runs, as long as the smoke clears quickly, I never give it another thought......