SailNet Community

SailNet Community (
-   Diesel (
-   -   Diesel Smoke (

MagicWoman 10-01-2012 08:37 PM

Diesel Smoke
I have a Perkins 4108 in very good condition and runs well. This weekend we did a 13 hour motor sail up the coast and engine runs great. At the end of the trip we stopped for about 2 hours and when we restarted I had a white/bluish smoke. Engine ran good, oil presssure good, no over heating. Moved the boat to a slip and smoke level lessened while running.

Oil level is same as start of trip. Next morning started up and ran well. Slight puff of smoke at start up and the clear.

Thinking it must be fuel related and possibly an injector stuck for awhile or fuel built up.

Magic Woman
Columbia 43

CalebD 10-01-2012 10:36 PM

Re: Diesel Smoke
What is the condition of the fuel in your diesel tank?
Gunk can grow in diesel fuel and could cause that symptom.

MagicWoman 10-02-2012 08:11 AM

Re: Diesel Smoke
I plan to add some Bio treatment to the fuel

bwindrope 10-02-2012 12:44 PM

Re: Diesel Smoke
Those symptoms sound exactly like leaking valve guides. First off, bluish smoke is oil. Black smoke is unburnt fuel. So you have an oil burning situation. That it didn't happen noticeably until after the engine had sat for a couple hours, tells me that oil had dripped down into the cylinders from the valve guides.

When an engine gets hot, as yours was after being used, oil is thinner and valve guides leak more. They are probably leaking a small amount all the time but not enough to produce real blue smoke. And small enough to not change your oil level.

The good news is that leaking valve guides are super common on older engines and need not require any action for quite some time. They do not themselves affect the engine performance, so long as you keep the oil topped off. Often, by the time the valve guides are going there are other things wearing out that may point to a rebuild or replacement, but you sound like she is running fine otherwise.

I once ran a VW for thousands of miles with leaking valve guides doing exactly like your boat, with no ill effects except for the environmental air pollution at start up.

MagicWoman 10-02-2012 12:57 PM

Re: Diesel Smoke
Thank you Aeolus.

I do not have any additives in the fuel. From what I am reading there could be water in the fuel. Does anyone have recommedations regarding addatives?

jameswilson29 10-02-2012 01:06 PM

Re: Diesel Smoke
Water in the fuel would not be the cause of the smoke; nevertheless, it is a good idea to avoid having water in your fuel tank by keeping the tank full as much as possible.

Check your primary fuel filter - may have a plastic/glass bowl at the bottom with a spigot/valve. It is the first filter from the tank, likely on the wall in the engine compartment; the secondary fuel filter should be mounted on the engine. Drain away water, sediment and cloudiness until fuel is clear (dyed red, of course). You should be changing your primary and secondary fuel filters no less often than annually.

I had my diesel fuel polished and my tank cleaned by a professional. Clean fuel is particularly important for a diesel engine.

dabnis 10-02-2012 03:56 PM

Re: Diesel Smoke

chucklesR 10-02-2012 04:07 PM

Re: Diesel Smoke
ahem...The web is our friend.

White smoke occurs when raw diesel comes through the exhaust completely intact and unburned. Some causes of this include

Faulty or damaged injectors
Incorrect injection timing (could be a worn timing gear or damaged crankshaft keyway).
Low cylinder compression (eg caused by leaking or broken valves, piston ring sticking, cylinder and/or ring wear, or cylinder glaze)

When white smoke occurs at cold start, and then disappears as the engine warms up, the most common causes are fouling deposits around piston rings and/or cylinder glazing. Use of our Flushing Oil Concentrate and FTC Decarbonizer address these respective problems.

Water entering combustion spaces will also create white smoke. Faulty head gaskets and cracked cylinder heads or blocks are a common cause of water entry, and are often to blame. Unfortunately, expensive mechanical repair is the only proper solution here.
Cost Effective Maintenance - Diesel Smoke tells YOU a Story...

My books from Calder say basically the same thing - I'm just too lazy to type it in.

Rockter 10-06-2012 07:34 AM

Re: Diesel Smoke
MagicWoman :

If you are starting fine, and not using oil, and the motor is pullung OK, I would not worry much.

13 hours without oil level drop sounds OK to me. That would be the equivalent of about 600 miles on the road. There is not much wrong, friend.

Before I re-bored it, my olde Volvo MD17C used to do in a pint of oil about every 8 hours. I used a gallon and a half across the Gulf of Mexico.

All times are GMT -4. The time now is 07:06 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging v3.1.0 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
(c) LLC 2000-2012

For the best viewing experience please update your browser to Google Chrome