View Full Version : Yanmar smoking

01-04-2009, 07:49 PM
I have some very light diesel smoke at idle from startup. It seems white to me. It continues even when the engine reaches operating temperature. It is very slight. I also see a very slight sheen on the water at the discharge so I believe it is unburnt fuel causing the light smoke. I have 3000 hours on my Yanmar 4JH2-HTE. I replaced the injectors and the problem continues. The engine otherwise performs great and starts easily.

I have not had to add oil between oil changes so I don't believe I'm burning oil but the smoke is so slight how would I know if I were burning just a bit?

Could it be the Turbocharger? Any ideas?

02-27-2009, 11:45 AM
"Whitish, whispy smoke from the exhaust may be an indication of poor quality fuel. To quickly verify this, get a jerry can with good, fresh fuel and a short length of fuel hose. Shut off the fuel at the tank, remove the fuel line from the lift pump, and connect up your short piece of hose, dunk the other end in the jerry can, bleed it through and run the engine for a while. If the smoke dissappears, you're on the right track. Carrying the jerry can and hose on board can be useful for bypassing a contaminated/faulty fuel system in an emergency too!

Hope this helps.