Visit our Popular Forums

Kenomac · 30-06-2015, 11:40

Question:

What could be causing the increased amount of soot coming out the exhaust outlets from our Yanmar 100hp turbo Diesel and our Westerbeke 10kw genset?

Both units are running better than ever, not burning any oil. We regularly revv the Yanmar once per hour per the owners manual to blow out the soot from the turbo, but this year, it appears we have more soot coming out. Before anyone gets too excited, we have a water separator for the exhaust which sends only the air exhaust to the outlets seen in the photo, the water is discharged below the waterline. What you see in the picture is three weeks worth of exhaust soot, mostly from the genset.

Could it be from the amount of bio diesel in the Italian diesel? I didn't notice nearly as much from the fill ups in Spain. We have an extensive fuel polishing system onboard and the diesel is crystal clear, nothing in the filters.

A knucklehead I used to work with, filled his Mercedes diesel in Massachusetts with biodiesel in his quest to save the planet... His car looked like a Burger King on wheels. You could see it smoking from a block away. Just wondering it something similar might be going on with the fuel... maybe a different mixture?

BTW: the shadow beneath the sooty exhaust is the rudder, not an oil slick.

Thanks in advance.

Ken

**Dockhead** · 30-06-2015, 12:53

You have the same engine, I have, and this may or may not be relevant, but mine smokes like a chimney, in addition to some soot. I almost didn't accept the boat when I bought it because of this, and drove the seller crazy with an army of mechanics and surveyors. The seller had the injection pump off and bench tested, overhauled the turbo, and did all kinds of other stuff to it, in an attempt to find the problem. The last surveyor, a well known master of diesel engines, came up with this scientific diagnosis of the problem:

SMOKY YANMAR

I have replaced all the injectors, and had the intercooler and all heat exchangers pulled off and cleaned out (at great expense) at various times, none of which made any difference.

It smokes less when well warmed up, and smokes less on the exquisite Russian diesel we bought in Vyborg, but otherwise never changes. I just got used to it. Engine runs great, starts great, and doesn't burn any oil.

DeepFrz · 30-06-2015, 13:00

I don't know how old your engines are but it may be time for an injector clean/adjustment. Just one idea. It may well be what Dockhead says, smoky Yanmar.

TeddyDiver · 30-06-2015, 13:18

Another thought that the engine doesn't get enough fresh air...

**Dockhead** · 30-06-2015, 13:19

Another thing -- my exhaust system is the same as yours -- water separator and below waterline release of water. Is yours a Halyard? My very boat was the model for the Halyard brochures, by the way.

dannc · 30-06-2015, 13:24

Is the fuel ULSD(Ultra Low Sulfur Diesel)?

I have two diesel engines, one in a truck and one on a tractor, and the only way I can see any soot is to quickly accelerate the engine. Well, ok, I don't do that on the tractor, but if I bog down the engine mowing, there might be a mere whiff of soot.

The tractor engine is a Yanmar. Neither engine smokes anymore compared to running on LSD(Low Sulfur Diesel).

Later,
Dan

Kenomac · 30-06-2015, 13:28

New injectors 600 hours ago, new turbo 250 hours ago, everything runs great, same soot from the non turbo Westerbeke.

Maybe... It's because the soot is more noticeable when not mixed with water? My old Hunter smelled the same, same color to the exhaust, but the engine exhaust was expelled mixed with water, so it didn't cling to the newly polished and waxed hull. With the separator, maybe the soot is just more noticeable?

**weavis** · 30-06-2015, 13:34

Quote:

Originally Posted by Kenomac

New injectors 600 hours ago, new turbo 250 hours ago, everything runs great, same soot from the non turbo Westerbeke.

Maybe... It's because the soot is more noticeable when not mixed with water? My old Hunter smelled the same, same color to the exhaust, but the engine exhaust was expelled mixed with water, so it didn't cling to the newly polished and waxed hull. With the separator, maybe the soot is just more noticeable?

Well.. in the absence of knowledge, I will just throw this question in........

Is it a monhull?

That made me laugh......
ahem... perhaps it want so funny..

(YES IT WAS)

Kenomac · 30-06-2015, 13:37

Quote:

Originally Posted by weavis

Well.. in the absence of knowledge, I will just throw this question in........

Is it a monhull?

That made me laugh......
ahem... perhaps it want so funny..

(YES IT WAS)

If I had a catamaran, my soot issue would be twice as bad. I'd need to spend twice as much time cleaning it off.

**Dockhead** · 30-06-2015, 13:38

Quote:

Originally Posted by Kenomac

If I had a multihull, my soot issue would be twice as bad. I'd need to spend twice as much time cleaning it off.

Perfect answer

**weavis** · 30-06-2015, 13:40

Quote:

Originally Posted by Dockhead

Perfect answer

Nonsense....... you would have engines that worked without problems due to heeling and flooding the water exhausts causing sooting .........

**weavis** · 30-06-2015, 13:41

LOL this could go on all night with the comments getting more and more outrageous......... wish I had time....... hahahahaha

Kenomac · 30-06-2015, 13:45

Quote:

Originally Posted by weavis

Nonsense....... you would have engines that worked without problems due to heeling and flooding the water exhausts causing sooting .........

Nope.... The genset creates the most soot of the two whilst sitting perfectly still in an extremely calm Sardinian anchorage.

**weavis** · 30-06-2015, 13:48

Quote:

Originally Posted by Kenomac

Nope.... The genset creates the most soot of the two whilst sitting perfectly still in an extremely calm Sardinian anchorage.

Like I said, I dont have time...... 2 more (quite sick) patients to see..... flu shot victims.........

Love the dog in your photo on your bio....... that made me smile too.