White Smoke From Gen Set.

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menzies

Guru
Joined
May 11, 2014
Messages
7,233
Location
USA
Vessel Name
SONAS
Vessel Make
Grand Alaskan 53
I have a 16KW Northern Lights Genny. This afternoon we turned it on to power the davit and launched the dinghy. I then went below to take a shower. When I came out of the shower I noticed the master cabin had some white smoke in it. I went upstairs and there was some smoke in the salon. I went into the ER and it was thicker. It did not smell of exhaust, or diesel, in fact hardly any smell at all.

We immediately turned off the Genny. I let all the smoke clear. Then I sat in the ER while my wife started the Genny and we let it run for about fifteen minutes. No smoke and the temp stayed around 185 where it should be.

We turned it all off as we we're going ashore. We got back about thirty minutes ago and started it up again. No smoke and no over heating.

I did some Googling, and one thing I found is that if your glow plug module malfunctions it can cause the Gen Set to smoke.

Can anyone help me understand why a glow plug malfunction would do that?

The other candidate is that the gen set is interlaced to the blowers. It won't start unless a blower is on. We have two "in" blowers and two "out" blowers. We always use the out blowers to take away the heat from the noise shield fan. This afternoon I may have turned on the in instead of the out. I will recreate that tomorrow to see what happens. That may explain the lack of smell.
 
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What they probably mean is that glow plug malfunction could lead to white smoke (unburnt fuel) on a very cold startup. However, it would clear up in seconds as the engine warms up. Also, that smoke would show up outside the boat.

Even though you said you did not smell any exhaust, I'd closely check the exhaust riser, shower head and all exhaust hoses and any muffler for a pin leak.

Until you have figured out where the smoke came from, don't run the generator while you are sleeping.
 
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Are you sure it wasn't coming from the electrical end? I don't like to be negative, but I had that happen on a genset once. It was not a good thing.
 
IF , during non use some water found its way into the exhaust , white smoke (water vapor) can take a long time to be evaporated.
 
White "smoke" that doesn't smell is probably steam from too much exhaust heat and too little raw water flow. The exhaust elbows corrode and degrade over time, and it's often not visible from the outside. Give it a good inspection which will probably require a mirror and light to get a good look. If there is ANY sign of corrosion, replace it. In fact, if the gen is more than 10 years old, just replace it anyway. NL makes a stainless version that is not much more expensive and holds up better.
 
I have a 16KW Northern Lights Genny. This afternoon we turned it on to power the davit and launched the dinghy. I then went below to take a shower. When I came out of the shower I noticed the master cabin had some white smoke in it. I went upstairs and there was some smoke in the salon. I went into the ER and it was thicker. It did not smell of exhaust, or diesel, in fact hardly any smell at all.

We immediately turned off the Genny. I let all the smoke clear. Then I sat in the ER while my wife started the Genny and we let it run for about fifteen minutes. No smoke and the temp stayed around 185 where it should be.

We turned it all off as we we're going ashore. We got back about thirty minutes ago and started it up again. No smoke and no over heating.

I did some Googling, and one thing I found is that if your glow plug module malfunctions it can cause the Gen Set to smoke.

Can anyone help me understand why a glow plug malfunction would do that?

The other candidate is that the gen set is interlaced to the blowers. It won't start unless a blower is on. We have two "in" blowers and two "out" blowers. We always use the out blowers to take away the heat from the noise shield fan. This afternoon I may have turned on the in instead of the out. I will recreate that tomorrow to see what happens. That may explain the lack of smell.




White smoke usually is from oil... dark smoke from fuel.... have you recently done any oil changes on the gen set? Perhaps sprayed some anti corrosion spray anywhere that might get hot?
 
White smoke without smell is water vapor. Exhaust leak or one heck of a Hollywood shower!
 
I agree with the others who said if you had white smoke that didn't smell it had to be water. If burned fuel or electrical smoke both would smell quite distinctly.

Ken
 
Any smoke that took a while to clear is almost certainly not water related. Also smoke in the engine room can be caused by an exhaust leak or bad blowby. Take a look at those sources first.


Any smoke in the exhaust, should stay in the exhaust.



David
 
Check for blowby. That can make a haze, often with little stink.

Also check that it did not overheat and expel coolant. Take actual pressure cap off the exhaust manifold and coolant level should be right there.

Agree that a burnout on stator, if that was the cause, the stink is incredible.

How good is your sense of smell??
 
How good is your sense of smell??

Just to put it in perspective, I came up to the Pilothouse ad looked into the salon and saw the haze. My wife was sitting there and I said "do you see that smoke?" She said "what smoke?"
I asked her to come up to the PH and look back and then she could see it in the sun shining into the salon. So really light and really no smell!

It as been running for the last couple of hours for laundry with the "out" blowers on - and no issues. I may take the sound shield off later and have a god look.
 
I may take the sound shield off later and have a good look.


That is the first thing I would do. Sound shields have been known to mask all sorts of problems that sometimes escalate into a disaster. On some gensets, Fischer Pandas notably, the raw water pump seal starts leaking and slings water all over the place. After a few hours of this, the engine and/or generator end is toast.



David
 
All resolved, for now.

Took the sound shields off and saw that the crankcase blow by vent hose was blowing the smoke. The area beneath the hose was slightly damp with oil. Took a video and sent it to my mechanic and he in turn discussed it with Northern Lights.
They suspect a leaking valve but it can wait until we get back. No danger and just run the out blowers when the Genny is running.

https://youtu.be/YGt8tMSkHes
 
All's well that ends well... Or doesn't end with a ruined genny!
 
Usually when you let the smoke out of anything electrical or electronic it has burned up. I guess it was bad engineer humor...
 
Usually when you let the smoke out of anything electrical or electronic it has burned up. I guess it was bad engineer humor...

I would agree somewhat since the alternative is replacing a 16KW genset! :)
 
Lucas make replacement smoke for their electrical components and harnesses. :)
But I agree,with an expensive large genset at risk, it`s not funny. At least you seem to be on track toward a diagnosis and fix.
 
My experience would tell me that white smoke w/o smell is definitely water vapor... Since it didn't repeat after you shut it off, I'd suggest that there was a plastic bag, sea nettle, or something blocking the intake thru hull which caused the genset to start to over heat due to reduced raw water flow... Then when you shut it down, the occlusion dropped off the intake which allowed the cooling water to flow again.

Kyle Hunter
MV DESTINY
DF 49 Euro
 
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