dry vs wet exhaust

[tn6437]

It may help to diagnose the source of your problem if you can determine which (or whether both) engine/exhaust is creating the sheen.

my boat is a single engine trawler. sorry for any confusion.

 

[BrianG]

I had a dry stack for 12 years on top of a 6v-53 Detroit. ZERO issues with soot. None. Dry stacks allegedly make the engine more efficient since less exhaust resistance and also a cleaner less corroded bilge since no salt water fumes backflowing into the boat. But they're noisy as hell. I much prefer wet exhaust for that reason.

 

[OldDan1943]

"pop test", the tech pulls the injector, puts them on a test rig, pumps up the pressure until it opens, visually inspects the fuel 'cone', bleeds off the pressure and watches for leaks at the fuel nozzle. There is a factory spec for the opening pressure. You may need a new spring, fuel nozzle or tip.
If you want more, there is a 'go no-go' tool which they can measure the nozzle diameter etc but, I would just verify the opening pressure and when closed, no leaks.

I would get a diesel tech for your brand of engine to remove, test and replace or in a hurry, they sell rebuilt injectors.

 

[ghost]

I replaced the injectors on one of my 3208’s a couple years ago. I still have a little oily surface when my engines run. I’m guessing we are just seeing a little oil past the rings or valve guides instead of diesel.

 

[rslifkin]

Some engines are just more prone to spitting crap out the exhaust than others. Even with my gassers, if the chokes are set a little too rich I'll get a hint of fuel sheen on the water behind the boat after a cold start from some of the less volatile components of the fuel not getting burned off completely.

 

[Delfin]

When I worked on Delfin back in the 70’s I recall the original owner, Don Tyler, commenting on fuel quality causing smoke and soot problems. He ran on cheap Mexican fuel a couple of seasons and sulphur content was high according to a lab test. But once he got back on better fuel that big Volvo was quite clean, maybe a short puff when he first lit it off. What a wonderful vessel you have there so much CCA cruising history and capability.

If you see us out and about, please flag us down. I'd welcome hearing about your work for Mr. Tyler on Delfin.


Carl

 

[friz]

Here is my approach to the wet or dry exhaust question. If you look at the riser the starter is directly underneath. Underneath that is a 2.5" hose dumping the raw water into the exhaust. As a matter of economy I had this riser fabricated at less than half the cost of a stock replacement from Germany. The exhaust/raw water exit through the transom.

 

[Gdavid]

Here is my approach to the wet or dry exhaust question. If you look at the riser the starter is directly underneath. Underneath that is a 2.5" hose dumping the raw water into the exhaust. As a matter of economy I had this riser fabricated at less than half the cost of a stock replacement from Germany. The exhaust/raw water exit through the transom.

Please share some pics of your Cargile Cutter, I've never seen one in person but find them interesting. I've never heard of a diesel powered one either.

 

[friz]

Please share some pics of you

I won't show you pictures of mine as it is in the middle of a complete restoration, V berth to the transom. The photo is of Sun Smiles - destroyed in a Wyoming wind storm being transported to Oregon. Beautiful boat. If you Google Cargile Cutter you will get lots of photos, interior and exterior. My boat originally had a Chrysler 318 V8 and a Volvo Penta outdrive. Both are gone. Not sure if the BMW diesel will fit. It is an in line 6. Preliminary measurements say "yes". The builder, Alan Cargile, made about 600 of these in the 70's. Various engines. He even made a few twin diesels. In 1977 he drove a twin diesel from NYC to Paris in 28 days, unassisted. Had around 1500 gallons of diesel. I guess that after that stunt he produced a few of his boats with diesel engines. Sadly closed shop around 1980.

 

[Gdavid]

Please share some pics of you

I won't show you pictures of mine as it is in the middle of a complete restoration, V berth to the transom. The photo is of Sun Smiles - destroyed in a Wyoming wind storm being transported to Oregon. Beautiful boat. If you Google Cargile Cutter you will get lots of photos, interior and exterior. My boat originally had a Chrysler 318 V8 and a Volvo Penta outdrive. Both are gone. Not sure if the BMW diesel will fit. It is an in line 6. Preliminary measurements say "yes". The builder, Alan Cargile, made about 600 of these in the 70's. Various engines. He even made a few twin diesels. In 1977 he drove a twin diesel from NYC to Paris in 28 days, unassisted. Had around 1500 gallons of diesel. I guess that after that stunt he produced a few of his boats with diesel engines. Sadly closed shop around 1980.

Good luck with the project, sounds interesting to say the least.