View Full Version : black smoke

12-06-2006, 12:36 AM
We are on our shake down trip so you will be hearing from us a lot.
When we got to Quartzsite AZ. from Connecticut the back of our tourmaster and our entire tow vehicle was covered with back diesel soot. Is this OK ????????

12-06-2006, 07:52 AM
Black soot from a diesel is normal to a point. It is usually caused by a over fuel condition or lugging the engine. In other words too much foot on the pedal trying to get up to speed or too much fuel going up a mountain.

Another thing I found is if one is using the "Economy" mode on the Allison tranny in hilly terrain the engine will produce more soot since the tranny doesn't downshift as fast and lugs the engine some.

But the late model diesel engines with the electronic controls don't produce near the soot as the older diesels did.

We usually have a dirty toad on a long trip that looks like a black soot exhaust coating. Our C7 CAT doesn't get the toad as near dirty as the '03 GS with the 3126 CAT did.

What engine do you have in your TM?

Help this helps answer you question.


12-06-2006, 10:29 PM
we have a 330 Benz engine.

12-07-2006, 10:27 AM
I don't have any experience with the MB engine, but would imagine it would be the same as far as exhaust coating the toad.

Maybe someone with an MB engine could jump in and tell us their experience with the toad being dirty/coated.


01-14-2007, 11:20 AM
hi from england
Is your MB a straight 6 or a v or a v8 twin or single turbo you might expect to get the odd soot mark up the rear but not to the extent you discribe it could be down to a faulty injector or a turbo fault or a blocked air filter go to the exhaust and get someone to rev the engine when hot check that the exhaust is not kicking out a lot of black smoke if it is then the engine is overfueling I dont know how old your engine is or even if it is the latest electronic injection engine what is the engine like for power and economy does it have an exhaust brake fitted and if so is it partially stuck closed in extream circumstances I have known the silencer box to be full of oil and soot but you would only expect this from a worn out engine with high mileage