Black, sooty,exhaust means?

[Dale Young]

I've noticed that when I put a load on my 2qm15 and throttle up , Some very black,sooty, smoke appears . It however, does'nt always do this. What does this mean?

 

[Gordon Torresen]

Black smoke

The speed of a diesel engine is determined by the amount of fuel being injected into the combustion chamber. Black smoke is the result of having more fuel than the engine can burn at a given RPM. When you have a load on the engine and increase the throttle, you are adding more fuel (to increase speed) but the engine takes a while to get up to the speed that can consume that much fuel. If you notice a diesel truck trying to accelerate, there is a puff of black smoke each time a new gear is found and the driver punches the pedal down. When the engine gets to a proper speed the smoke is gone. Sustained black smoke, regardless of engine speed indicates internal injection problems or a continuous overload (over throttle).

 

[Bob Haskell]

Got enough air?

A somewhat overlooked cause to this problem is a restricted air flow,producing a incomplete combustion process that will also cause black,sooty exhaust smoke,this from a shade tree mechanic but I believe it to accurate. Sincerely.Bob S/V Blackmist

 

[Barry]

sooty exhaust

I had the same problem. I checked the prop and found it was terribly fouled. once cleaned, the black sooty exhaust stopped.Good luckBarry