White Smoke

[Alden68]

At start-up, when the engine is cold, I have a significant amount of white smoke. After things heat up the problem goes away entirely. I have researched N. Calder's book and there are like 10 possible problems.

Can anyone shed some light on this and help me narrow down my next expense.

Thanks

[sailingdog]

Alden88

It would help if you told us what kind of engine your boat has to begin with. Also, how the engine is cooled would help as well.

[Alden68]

1968 Perkins 4-107, heat exchanger

[tigerregis]

Which ones have YOU eliminated?

[sailingdog]

Damn tiger... that was my next question...

[sailingdog]

Just curious, how old is your fuel??? And how long does the white smoke last for??

I know that that white smoke can be an issue at startup if the fuel has a lower cetane rating (basically the inverted diesel counterpart of octane in gasoline—the higher the cetane rating the more resistant to ignition the diesel fuel will be and the higher the temperature it will ignite at—at lower temperatures, the white smoke is often made up of uncombusted fuel). This can be the case if you buy fuel from a less than reliable supplier or if the fuel is getting old IIRC.

[yotphix]

Many diesels smoke white on startup. In many if not most cases it is not really a problem at all, especially if it goes away as the engines heat up. The monster 12 cylinder MTU's I am responsible for put out so much white smoke on a cold start that the fire department was called by a well intentioned observer. We have since installed block heaters to completely alleviate the problem. (The US navy uses the same engines and has the same "problem")

Do they still produce white smoke if you restart them when they are warm?

[bestfriend]

Alden - It might not be anything. On a regular gas engine it usually means you have a leak between the coolant and the oil, like the head gasket. The white smoke will get worse until it smokes all the time. On a diesel engine, you can have a little white puff if the engine has not been run in a long time. Usually a by product of the fuel. Mine does it if I go a month without starting, but if I start it up every couple of weeks or more, no smoke. If it puffs white when its warm, you may have coolant in your oil. Blue smoke is the biggest problem. Here:

The answer is in the smoke.
We can generally understand what is wrong with a diesel engine by the colour of smoke emitted from the exhaust. There are three basic colours - black, white and blue.

Black smoke
This is due to a air to fuel ratio imbalance, either the fuel system is delivering too much fuel into the engine or there is not enough clean air (oxygen ) a few things to look for :

* Faulty injectors (injectors need attention at about 100.000 to 120 000 miles)
* Faulty injector pump
* Dirty air cleaner
* Turbocharger or intercooler faulty
* Problems within cylinder head, valves clogged up due to faulty EGR (exhaust gas recycling unit)

White smoke
Normally means that the fuel injected into the cylinder is not burning correctly. The smoke will burn your eyes.

* Engine/pump timing out
* Fuel starvation to the pump causing the pumps timing not to operate correctly
* Low engine compression
* Water/petrol in the fuel

Blue smoke
The engine is burning engine oil

* Worn cylinders or piston rings
* Faulty valves or valve stem seals
* Engine over full with engine oil
* Faulty injector pump/lift pump allowing engine oil to be mixed with the diesel

Alden- if you can, start it every day and see if the problem goes away, and restart it after it is warm and check for smoke.
also, you can take a sample of the oil in to have it checked.

[camaraderie]

Ditto Yotphix! There is no problem if the smoke goes away as Alden reports. Just water vapor...like fog!

[bestfriend]

There is a difference, however, between a thin white smoke with no odor, and a thicker, funny smelling white smoke. The first is, like you said, just condensation, but the latter is to be concerned about.