White Smoke on Diesel Engines

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ChrisL

Veteran Member
Joined
Jan 31, 2015
Messages
42
Location
US
Vessel Name
Morning Star
Vessel Make
Defever 41
Hi All,

Lately I have been getting white smoke from the exhaust. I had the injectors cleaned about a year ago and the engines run well. No black or blue smoke, just white. Even after warm up it's still blowing white smoke.

I am running twin Isuzu 6bb1 diesel engines that have 3000+ hrs. These engines perform well, no oil leaks or loss of any oil.

Thoughts?

Thanks,
 
Quick question did you have white smoke before you cleaned the injectors and when the injectors were cleaned did the smoke go away ?
 
White smoke was there before the injector cleaning and after, but it's worse now.
 
New Pope elected?
 
Here is an interesting article written by Tony Athens on just this subject.
These articles are all part of a knowledge base called Tony's Tips and they are interesting reading. For those who don't want to wait until the end...Tony says that white smoke is unburied fuel. Go ahead and read the article!
Bruce

What is white smoke? - Seaboard Marine
 
Here is an interesting article written by Tony Athens on just this subject.
These articles are all part of a knowledge base called Tony's Tips and they are interesting reading. For those who don't want to wait until the end...Tony says that white smoke is unburied fuel. Go ahead and read the article!
Bruce

What is white smoke? - Seaboard Marine



Tony Athens must be an amazing guy he agrees with #4:D
 
Unless of course the white "smoke" is really steam.

Right, this is worth investigating too. Is it from both engines equally? Do they share a common raw water intake? Or perhaps a sea chest?

Restricted raw water flow will cause what water there is to overheat. You can check the temp of your exhaust elbow and hose immediately after the elbow with an IR temp gun. Look for hot spots.
 
Unless of course the white "smoke" is really steam.

If steam, it will dissipate after a boat length or two. If unburned fuel it will hang around longer and smell.

As Twistedtree hints, if steam, a good thing to check is the raw water intake openings, especially if you have the DeFever sea chest design. Close the valve and pull a hose off, looking for a white scale buildup.
 
And did it only start happening when the fall air temperatures dropped so that the temp of the exhaust is now significantly warmer than the air temp?
 
Thanks All. I will read the article and start some investigative diagnosis. Each have their own intake and the steam idea is interesting, but we are in San Diego and it might be too warm for steam.

I did get very close to running aground in some shallow waters near Coronado Bridge, so maybe the sea strainers are clogged, although water was coming out of the exhaust.

We'll start em up this weekend and see what it looks like. Maybe I'll post a Gif as an example.
 
I read the article and the author mentioned fuel quality. I am getting low and was going to fill it up this weekend. I guess I was down to the last 20 gal+- of a 250 gal tank (40 gal / 500 gal).

So much to consider...
 
Check your exhaust temperatures. Check water flow at outlet. Does the white smoke appear immediately (fuel) after startup or only after the engine warms up (overheating). White from fuel has a strong odor.
A friend went thru this during the summer. Injectors cleaned, no change. Injectors rebuilt, problem solved.
 
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There is also an article on Boat Diesel talking about different exhaust smoke written by Peter Compton. Basically the caused may be low compression, fuel system problems or too low temperature running.
 
I had white smoke on the port exhaust, after much searching found the culprit in the port raw water intake valve on the sea chest.
This was shortly after the PO had all the sea valves serviced at a "yard".
The buildup was rock hard and had to be chiseled out. Once cleaned, no mo white smoke.

Bill
 

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IMO steam from insufficient raw water flow or mixing is the first suspect.. If you can find a way to smell it it will be obvious if it is diesel or water,
 
I have 3208T/As with around 2000 hours. I do not have glow plugs. Mine smoke a lot on engine start up and disappears after warm up. I also found that after running 200 miles at 2100 RPMs the engines are nice and clean and purring.....
 
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