Diesel engine "excessive smoking"

[Paul Waine]

I have a CD-25D with a Yanmar 1GM 9 h.p. engine which seems to be smoking excessively. This happens at all rpms, maximum 3000 cruise at 2500. Is this unique or does everyone have this problem? I would appreciate any feedback, comments and suggestions. Thanks.



pwaine@nantucket.net

[Stephen]

I have a CD-25D with a Yanmar 1GM 9 h.p. engine which seems to be smoking excessively. This happens at all rpms, maximum 3000 cruise at

Diesels are not supposed to produce visible smoke. What color is the smoke? And how old is the engine?



sailing@star.net

[Bob Miller]

I have a CD-25D with a Yanmar 1GM 9 h.p. engine which seems to be smoking excessively. This happens at all rpms, maximum 3000 cruise at 2500. Is this unique or does everyone have this problem? I would appreciate any feedback, comments and suggestions. Thanks.

Paul...generally, smoking from a diesel is of three types:
a. White smoke - usually indicates the presence of waterduring the injection/ignition phase.
b. Blue smoke - indicates crankcase oil in the exhaust. This is usually due to a piston or piston ring or cylinder wall problem.
c. Black smoke - this is usually the easiest one to correct. It usually indicates unburned diesel fuel. Check the following:
1. Worn injector.
2. Fouled prop or barnacles on your prop.
3. A lot of weeds growing on your boat bottom.
4. A misalignment of the prop shaft and the engine shaft.

The smoking may not be caused by one of the above, but they are easy to check, especially #2 & #3. Good luck, and let



millerfam5050@worldnet.att.net

[Geoff Safron]

This is possibly incidental to your question about the smoke itself as an indicator of problems; my 13 hp MD7A doesn't produce any visible smoke, but the exhaust sullies the stern wake such that I have a 3-inch band of black to clean off her stern at the end of each day; is this a normal chore for everybody, or would this constitute a form of "black smoke", and something I should look into?

Sencondly, recommendations for anyone's favorite cleaning product(s) for the stains caused by diesel exhaust?; despite my daily cleanings, there appears to be a cumulative staining of the paint/gelcoat that isn't coming off. This is tarnishing my beautiful stern lettering job, durnit!

Thanx,
Geoff



Brainstorm@Unidial.com

[Stephen]

I have the same problem. I don't think there's a problem with the engine, but I hope someone has a solution for preventing, or at least cleaning, the mess!



sailing@star.net

[RON BRASSORD]

This is possibly incidental to your question about the smoke itself as an indicator of problems; my 13 hp MD7A doesn't produce any visible smoke, but the exhaust sullies the stern wake such that I have a 3-inch band of black to clean off her stern at the end of each day; is this a normal chore for everybody, or would this constitute a form of "black smoke", and something I should look into?

Sencondly, recommendations for anyone's favorite cleaning product(s) for the stains caused by diesel exhaust?; despite my daily cleanings, there appears to be a cumulative staining of the paint/gelcoat that isn't coming off. This is tarnishing my beautiful stern lettering job, durnit!

Thanx,
Geoff

I had the same problem with my older Morgan 38 --repeated staining from the Perkins 4/108 . I switched to using nothing but a higher cetane fuel [Hess] brought in in clean jerry jugs. The engine ran noticeably better and no more stains . Can'y hurt to try it.
Ron Brassord Lighthouse Pt Fl

[Jon Larson]

Geoff,

I get the same smudging from PERI, particularly when I'm motor sailing and the water is boiling up around the stern. It has done that for as long as I've owned the boat.

I use my boat wax/cleaner to clean it off, does a good clean job.

Jon Larson
Cape Dory 30 PERI
San Francisco Bay

This is possibly incidental to your question about the smoke itself as an indicator of problems; my 13 hp MD7A doesn't produce any visible smoke, but the exhaust sullies the stern wake such that I have a 3-inch band of black to clean off her stern at the end of each day; is this a normal chore for everybody, or would this constitute a form of "black smoke", and something I should look into?

Sencondly, recommendations for anyone's favorite cleaning product(s) for the stains caused by diesel exhaust?; despite my daily cleanings, there appears to be a cumulative staining of the paint/gelcoat that isn't coming off. This is tarnishing my beautiful stern lettering job, durnit!

Thanx,
Geoff

jon9@ix.netcom.com

[Homer Cox]

I have a CD-25D with a Yanmar 1GM 9 h.p. engine which seems to be smoking excessively. This happens at all rpms, maximum 3000 cruise at 2500. Is this unique or does everyone have this problem? I would appreciate any feedback, comments and suggestions. Thanks.

I too have a 25D that smoked up the transom. My solution was to slip a PVC coupling over the exhaust wwhich extended it out by about 2 inches. Result - No more smoked transom.



HomerCox@Worldnet.att.net

[Jerry Le Cocq]

I have a CD-25D with a Yanmar 1GM 9 h.p. engine which seems to be smoking excessively. This happens at all rpms, maximum 3000 cruise at 2500. Is this unique or does everyone have this problem? I would appreciate any feedback, comments and suggestions. Thanks.

The injector pump has no control for the amount of fuel supplied to the injector. Since the engine is getting to much fuel you can reduce the amount of fuel some what by rasing the injector pressure. It may be to low or out of the specified range now. Yanmar has told me that they set the injector pressure to 200 psi. Some dealers have told me that they set it in the 200-275psi range. This is accomplished by using shims in the injector on the spring seat. Pull the injector and install the shims yourself or take it to any diesel repair and they can set it to anything you specify.



jlecocq@milehigh.net