what' up with these CATs

[captian]

HI to all,
Just wanted to ask a question. I've got a 1986 viking 35' convertible with 3208 cat 320 hp. turbo charged. After long runs from home port Brick town NJ to the 100 square and back I've got so much soot on the back bulk head and the transom that it takes me about a week to clean it off. I've changed filters and cheched all engine fluid levels, but not sure why this keeps happening. Engines run well, both reach full RPM no problem, but when first getting up on plane a black cloud of smoke trails for about 30 seconds then clears to a faint trace when looking over the horizon.
What could this be? Can the lack of side vents cause this problem? These are not the 375 3208 CATs with after coolers.

[gofshn]

check your aftercoolers to ensure they are clean if you haven't already

[clt_capt]

Originally Posted by captian

HI to all,
Just wanted to ask a question. I've got a 1986 viking 35' convertible with 3208 cat 320 hp. turbo charged. After long runs from home port Brick town NJ to the 100 square and back I've got so much soot on the back bulk head and the transom that it takes me about a week to clean it off. I've changed filters and cheched all engine fluid levels, but not sure why this keeps happening. Engines run well, both reach full RPM no problem, but when first getting up on plane a black cloud of smoke trails for about 30 seconds then clears to a faint trace when looking over the horizone.
what could this be? Can the lack of side vents cause this problem?

I'm currently working with Cat on the same issue with my boat - Luhrs 36 w/ Cat 3126 420HP engines. I think we are getting close after about 2 years...

So far,
Replaced air filters
Cleaned Aftercoolers
Replaced injectors
adjusted timing

It looks like the main cause was a turbo boost assist hose which came loose - I don't understand how it was missed with all of the above, but Cat is fixing it.

Has your boat always done this? Mine only started after I had to replace one of the turbos.

[hotshot1]

I get it too with my diamond cummins. deal with it get a wax restorer takes 10 minutes to clean after 50 hours

[Reel life]

sounds like a restricted air filter or fuel filter

also if you lugg a diesel it will smoke
are you sure you are not turning to big of a screw

[Deep C]

Purple power will clean the mess just fine. Get it at home depot... Have a similar issue with cat 420 engines in a luhrs... A simple solution may fix the luhrs issue... Seems that the designers forgot to ventilate the engine room when they made it... Engines can't suck enough air or at least are having a harder time breathing. We reversed the blower last trip to see if that would help and it did. Another thing that helped was jacking the rpm just a touch from where the owner had been running them. Fuel economy improved boat planed a bit better and ran cleaner...
So you could vary the throttle a touch and make sure she's breathing right as a start...

[captian]

The boat was a Cape May nj charter boat before I got it. It was call Reel Sweet, now named Miss MIgadalia. All records show that the props were MRI'd and corrected where needed the boat does about 21knots at 2400 RPM, all out she'll do 25knots at about 2650 RPM. Any one know of the history of this vessel? I was told it was used in charter for mainly striper fishing, boat shows well and runs great but just that soot?

[gottaflylee]

We don't have Cats but almost the same thing. Turned out to be 2 things. Sticking injector and turbo problem.
Now as to your soot...get you some "Greez-off to clean your transom. Just spray it on, let it sit for a couple of minuets and with a soft brush lightly scrub and rinse with water, works great for me...

[captian]

Did the sticking injector cause a change in engine performance? I think my engines are running fine?

[Deep C]

Injector issues I have had really didn't affect the running but you could see a trail of dirty exhaust behind the boat for a long way out. Could well be part of an issue... If you are black smoking when you throttle up it can be a case of pushing the throttles up too quick. Whats happening there is you are pumping a lot of fuel but the rpm hasn't yet come up to provide enough air flow... If its happening if you throttle up slowly, then you are loading the engine... That being maybe a dirty bottom. Too much prop. Too much weight. Not enough or too much trim. Air filters clogged. Turbo not providing all the boost it can...
Most boats will soot up to some degree on long runs. I worked for Dale Earnhardt when he was alive. Engines were in impeccible shape all the time. Still on a 140 mile run from Palm Beach to Chub Cay we'd pretty well have a good layer of slime even up on the bridge and my tee shirt would get pretty grey...