Generator White Smoke

[RussWhite]

The attached picture should show the white smoke I am getting when I run the generator. I do not boondock, so the only real exercise it gets is on trips and a monthly or so run for a half hour to make sure it starts and works okay. I must admit I have not paid much attention to the smoke as each time it starts easily and seems smooth and does its job. But, I am concerned that this much white smoke is not normal. The smoke does not seem to get any less as time passes. The generator reaches an indicated water temperature of about 175 and oil pressure is around 60.

I'm not too familiar with diesels, but was under the impression that they are an excess air engine and should basically combust all the fuel injected in each cylinder if the cylinder is healthy. I thought I would try and get an exhaust temperature for each of the cylinders at the exhaust manifold with my infrared temperature gun, but there was too much insulation wrapped in the area to do that. So I have this uneasy feeling something is not right, but no idea what to do about it.

All thoughts and ideas will be appreciated. Russ

[prairieschooner]

Could be normal if it is cold. How is the Coolant Level? White smoke usually indicates moisture.

[RussWhite]

Eighty-five degree ambient, 175 for coolant, radiator full, coolant less than a year old. I don't think it's moisture but I will keep a close eye on coolant. Thanks, Russ

[Richard and Rhonda]

Russ,

You may have an injector that is not spraying cleanly. The first thing I would do is put the generator under load to get it hot. We hardly ever run them near capacity, and diesels don't like to idle. Before I removed injectors, I would turn all the AC's down as low as they will go and run them off the genny. The idea is to get some load on the engine and burn off any crud on the injector tips.

I am assuming you have checked the air filter and it's clean.

Also look around the little turbo on the exhaust to make sure you aren't losing turbo boost.

I posted earlier about how much better mine ran after removing and cleaning the injectors in addition to adjusting the valves. It was not a difficult job at all. The hardest part is disconnecting the slide from the pneumatic cylinder so you can get easy access to the motor. That would be my next step if the blowing out the soot approach didn't cure it.

[RussWhite]

Follow up...

Thanks Richard for your thoughts and ideas. First I removed the air filter and while not pristine it was looking pretty good to me. I really did not know how you wanted me to check the turbo, so I just removed the hose between the outlet of the filter canister and the inlet of the turbo. I stuck my finger in there and it spun freely. I then fired it up and watched it spin with the aid of an inspection mirror. I returned the generator to its normal running position and set the air conditioners to ice cold and turned on the AquaHot selecting electric only and it was all the way cool. I had a good load going on the generator and I then went outside to observe the exhaust. It looked clear and I thought, that was easy. Must be the air filter, but soon things changed and the smoke was back. I think in the past I just hand not looked at the exhaust that soon after it started. Well I planned to follow your advice and let it have a long run and get good and hot. While watching I occasionally noticed bits of black popping out of the exhaust pipe. I then looked around and there were carbon bits everywhere. See the picture of my car covered in the stuff. I wasn't feeling too good at this point, but the generator continued to purr and coolant and oil were just where they should be on the gauges.
Now it's hard for me to just let the fuel be consumed when I could plugin, but kept telling myself this was probably the thing to do.
The second picture shows the final result as the smoke eventually stoppped completely as did the carbon bits. There are no more boats going by and pointing to the roof of my bus:) Thanks - Russ

[chockwald]

Russ, what a great outcome. Richard is the man!

[tuga]

Follow up...

Thanks Richard for your thoughts and ideas. First I removed the air filter and while not pristine it was looking pretty good to me. I really did not know how you wanted me to check the turbo, so I just removed the hose between the outlet of the filter canister and the inlet of the turbo. I stuck my finger in there and it spun freely. I then fired it up and watched it spin with the aid of an inspection mirror. I returned the generator to its normal running position and set the air conditioners to ice cold and turned on the AquaHot selecting electric only and it was all the way cool. I had a good load going on the generator and I then went outside to observe the exhaust. It looked clear and I thought, that was easy. Must be the air filter, but soon things changed and the smoke was back. I think in the past I just hand not looked at the exhaust that soon after it started. Well I planned to follow your advice and let it have a long run and get good and hot. While watching I occasionally noticed bits of black popping out of the exhaust pipe. I then looked around and there were carbon bits everywhere. See the picture of my car covered in the stuff. I wasn't feeling too good at this point, but the generator continued to purr and coolant and oil were just where they should be on the gauges.
Now it's hard for me to just let the fuel be consumed when I could plugin, but kept telling myself this was probably the thing to do.
The second picture shows the final result as the smoke eventually stoppped completely as did the carbon bits. There are no more boats going by and pointing to the roof of my bus:) Thanks - Russ

Russ,

My generator does the same thing; white smoke and bits of black carbon come out of the exhaust. I change my air filter every time I change oil and filters. I re-read your post, but I can not figure out what you did to make it stop smoking? Did you change the air filter? Or did disconnecting the hose that goes from the air filter cannister to the turbo do the trick? Or did just running it with a heavy load do the trick?

Thanks,

[RussWhite]

Russ,

My generator does the same thing; white smoke and bits of black carbon come out of the exhaust. I change my air filter every time I change oil and filters. I re-read your post, but I can not figure out what you did to make it stop smoking? Did you change the air filter? Or did disconnecting the hose that goes from the air filter cannister to the turbo do the trick? Or did just running it with a heavy load do the trick?

Thanks,

Tuga,

It's my opinion that the full load operation for an extended period of time did the trick. Did you see the after picture? I could not even tell it was running from looking at the exhaust. I was one happy camper. And to be clear, at that point in time I had not reinstalled the air cleaner and hose to the turbo. There was a long period of operation ( 1.5 hours ) with smoke and soot and then it cleared with no other changes being made during the run. I will report back if there is a recurrence on the next run.

[prairieschooner]

OK Guys,
This would appear to have been moisture that was burning off as the Diesel Engine for the AC Electric Generator cam up to temperature and burned it off. I would think that if the Air Filter was Dirty then it would have Chocked off the Air causing it to run Rich, this most likely would have caused Black Smoke.
Anyway this may simply be a normal situation when starting a Diesel Engine and waiting for it to come up to Temperature. By the way if this was to continue or be persistent then it could indicate a Head Gasket Failure.

[busnut]

White smoke from a diesel happens often with a cold engine.

But you have the roof exhaust and a very long exhaust pipe. My guess is you simply had built up water in your exhaust system. Also carbon. Running your genset and getting it hot for a period of time simply cleaned out the exhaust pipes.

[Wally Arntzen]

Great news that you have it running and sounds like it's running well.
Over the years I have spoken to several generator engineers and mechanics and all of them said that the worst problem with generators is not using them. I have several friends with many brands of coaches who try to save fuel by not running the generators and when they need them they either don't start or they run very badley.
When i'm on the road I suspect that my generator is running 80 percent of the time, especially in the hot weather due to the dash air not being worth didley squat.
It's just when I go my doctor and he tells me to use it or lose it, run it and run it with a load like you did to clean it out.

[Richard and Rhonda]

I have been traveling, hence the delay.

It is my observation from having the same issue with my own gennie that coincided with many hours of running at a light load that I commented upon.

Since it was approximately 30 degrees at the time and the AC wont work that low, plus I was already intoxicated with diesel oil from the main engine debacle, that I decided to adjust the valves and look at the injectors.

What I found was the injectors were completely covered with a layer of carbon about .030 thick. Also, and more telling, was the hole into the cylinder head had a crust of carbon plugging it up even after I removed the injector. I used a brass rod to break that up.

The point is I had visible proof of what happens when you run the gennie at light loads for extended periods.


Ok, one more point. I agree to a certain extent that water vapor can create white smoke. However, unburned or raw diesel will also be white. Partially burned diesel will be black. I think what you were seeing when you first cranked the engine was raw diesel, and when the engine heated a bit the raw diesel then turned into partially burned, i.e. black and sooty diesel. Of course all of this comes from the diesel not atomizing finely enough through a fouled injector.

When I had the cracked liner in the main engine there was NEVER any white smoke. The water simply does not flow into the high compression of the cylinder while the engine is running.

I am glad that the run it hard remedy was effective. A couple of gallons of diesel is certainly cheaper than an hour of a mechanics time. However, if the problem persists, you may want to have the injectors replaced or rebuilt.