Community Forums

tricotec · 06-10-2015, 08:27 AM

Our 2005 Windsor with Cummins ISL400 began to blow Black Smoke when accelerating on this trip. It seems to be accompanied by a slight loss of power, but not too much. Turbo boost pressure seems normal. No warning lights or alarms on the engine and all parameters seem normal.

Our last fueling we noticed the fuel we were pumping looked a little more syrupy and darker in color than usual. (after we pumped...LOL)

Could this be a fuel quality issue?

Anybody have any advice?

DMTTRANSPORT · 06-10-2015, 08:32 AM

Quote:

Originally Posted by tricotec

Our 2005 Windsor with Cummins ISL400 began to blow Black Smoke when accelerating on this trip. It seems to be accompanied by a slight loss of power, but not too much. Turbo boost pressure seems normal. No warning lights or alarms on the engine and all parameters seem normal.

Our last fueling we noticed the fuel we were pumping looked a little more syrupy than usual. (after we pumped...LOL)

Could this be a fuel quality issue?

Anybody have any advice?

Fuel Filter(s) Bad fuel usually results in lack of power/lousy mileage

tricotec · 06-10-2015, 08:34 AM

Just so I understand, how does a clogged filter make the engine smoke? By starving it for fuel?

Diesel's are new for us, so I'm striving to understand.

JMonroe · 06-10-2015, 10:55 AM

In my very short career at a diesel truck dealer in the '70s a mechanic told me the first thing he'd check for a smoking issue is the air filter. Restrict the amount of air getting to the engine at especially higher throttle positions and you end up with too much fuel relative to air (rich) and black smoke.

Mike Canter · 06-10-2015, 11:13 AM

You ask about how a blocked fuel filter can cause black smoke. Well Diesel engines as far as lean and rich indications are reversed to gasoline motors. On a gasoline motor if you pull out fuel it goes lean and runs hotter. In a diesel it takes fuel to make it run hotter so going rich in a diesel puts more fuel in the cylinder and can burn up the motor if too hot. So if the fuel filter is restricting the flow and not putting fuel in the cylinder the combustion temperature cools down and you don't get complete combustion and that results in black smoke. To tune a diesel you add fuel until the EGTs heat up to 1300-1330* F

Rburian · 06-10-2015, 01:43 PM

Check if the exhaust brake value is stuck closed, I had a similar issue and determined the pin holding the valve fell out resulting in s closed valve, black smoke was pouring out the exhaust and lost power.

normandlegra · 06-10-2015, 02:02 PM

My first mh, was a DP with a small 5,9 L ISB CUMMINS engine and if the r.p.m. were below 1700, it was smoking black mainly going uphills; running it in a lower gear, let say 5th gear instead of 6th gear, the r.p.m would reach 1800-2000 and that CUMMINS was running really great.

Mike Canter · 06-10-2015, 02:55 PM

That was pretty normal for the early diesels with mechanical injection to smoke under heavy load or when it shifted gears. The ISL400 has electronic fuel injection and controls and should not smoke othe than a little while climbing steep grades.

tricotec · 06-10-2015, 08:26 PM

Quote:

Originally Posted by Mike Canter

You ask about how a blocked fuel filter can cause black smoke. Well Diesel engines as far as lean and rich indications are reversed to gasoline motors. On a gasoline motor if you pull out fuel it goes lean and runs hotter. In a diesel it takes fuel to make it run hotter so going rich in a diesel puts more fuel in the cylinder and can burn up the motor if too hot. So if the fuel filter is restricting the flow and not putting fuel in the cylinder the combustion temperature cools down and you don't get complete combustion and that results in black smoke. To tune a diesel you add fuel until the EGTs heat up to 1300-1330* F

Thanks for the detailed technical explanation. I am an engineer as you might guess. I will replace all the filters...they are a little overdue anyway.

Miramichi · 06-10-2015, 08:36 PM

First thing I would think of is low quality diesel or possibly even coloured diesel. I have seen coloured diesel being pumped out of the "premium" tank before. If so, be warned, it will cause a lot of smoking and wreck havoc on filters. Hopefully you have burned through it and can get your hands on some decent grade diesel (if the issue). I before E except after C and especially while spelling diesel.

Mike Canter · 06-10-2015, 08:43 PM

Bobby, I might add that diesel filters are required to be changed more often than gasoline filters. The norm is at 10,000 miles. You should have two fuel filters. I always carry a spare set of fuel filters with me. Are you a retired Boeing engineer since you list home as being up there?

tricotec · 06-12-2015, 03:00 PM

Quote:

Originally Posted by Mike Canter

Bobby, I might add that diesel filters are required to be changed more often than gasoline filters. The norm is at 10,000 miles. You should have two fuel filters. I always carry a spare set of fuel filters with me. Are you a retired Boeing engineer since you list home as being up there?

I'm under on the mileage, but over on the time requirement (1 yr). I've not put much mileage on, so I deferred changing them for a while. I have a full set of filters which are going on before it moves again.

Mike Canter · 06-12-2015, 03:34 PM

I don't change filters based on age only on mileage but each to his own. Can't understand how a filter can get clogged up if no fuel flowing through it unless you have Black Slime in the fuel tank. In your case it is probably good to change filters and see if that fixes it. Normally if something is wrong in the motor you would have a check engine light. You may want to carefully cut open the first or primary filter and take a look at it and see if there is anything that has blocked it. Having the filter stained heavy black is normal as long as no good black slime.

walt2137 · 06-12-2015, 08:21 PM

Quote:

Originally Posted by Miramichi

First thing I would think of is low quality diesel or possibly even coloured diesel. I have seen coloured diesel being pumped out of the "premium" tank before. If so, be warned, it will cause a lot of smoking and wreck havoc on filters. Hopefully you have burned through it and can get your hands on some decent grade diesel (if the issue). I before E except after C and especially while spelling diesel.

Step it is the same fuel they just add a dye to show it s not road taxed, my sons fishing boat has a Cummins Diesel engine and so does my grand son twin Diesel engine boat and it is not a problem for them or me with my two diesel tractors. I also ran it in our coach after the storm in 05 as that was all we could get in the MS and LA coast area, and no problem with the engine.