white smoke in exhaust

[SeaSteward]

I think I know what it is but- my Yanmar diesel is smoking white, and the oil volume is appearing to increase. Head gasket? Its running fine, but Im worried as the boat is halfway up the coast. Can I replace the hgead gasket myself- I cant mill it if it is warped- but I dont think it ever overheated. I defintely take care of this amazing engine.

thanks

[Faster]

If FWC is your coolant level down? White smoke is often from antifreeze being burned... which also points to a head gasket problem...

Replacing the head gasket is not rocket science.. but it would be real nice to have an engine manual on hand when you do it. And the required tools, of course.

[Rockter]

Is the oil changing colour to a mustard-green-cream?
If it is, then the coolant has been breached.
Catch some of the exhaust water in a bucket and have a look also.

[jrd22]

I agree with Faster and Rockter, could be head gasket. Do the checks suggested and see if you have coolant in the oil or exhaust or the bilge. White exhaust can also be unburned fuel, from bad injector(s) usually. This can dump enough fuel into the cylinder sometimes that you will get diesel in the crankcase which dilutes the oil and it will raise the level on the dipstick. What kind of engine is it?

John

[camaraderie]

Other possibility is a breach in the oil cooler exchange if you have one.

[lharmon]

Before ripping off your head gasket check your cylinder compression for varience. Your smoke could be as simple as air in your lines or a bad load of fuel. A manual is a great thing to have. Calder's Marine Diesel Engines is a great reference as well. For Yanmar I would call Max Boring in NJ.

Not to scare you but if it is bad your head could be cracked and should be inspected by professionals. You do not want to do all the work for no gain. I believe the inspection is called dynafluxing? Someone here will know all about it.

Sorry for your difficulty. Best of luck and let us know how you make out.

LH

[lharmon]

Oh I forgot to add this but my 2 gm started smoking and we finally found a partially engaged decompression lever. I had been trying to hand crank it and thought I had ruined the motor! When I realized there were two of the levers I found I could crank it quite well. I had been only releasing one cylinder. It looked like we were trying to lay down a smoke screen albeit a wimpy one as the engine is only 13 horsepower. Maybe this is more appropriate for a dumb moves thread but thought it might help you.

[kiprichard]

I'm no deisel mechanic but I did take a marine deisel course. We were told white smoke is just about always unburned fuel and it's seldom good.

[Rockter]

Black smoke is unburned fuel, is it not?

[MARC2012]

Was taught both previous correct.White usually caused by low compression or faulty injector/s.Black normally when turbo egages then stops.