Looking for insight on what I am getting grey smoke from my engine, about 1700 hrs.
Runs smooth, starts great.
What needs do be dome to resolve?
Runs smooth, starts great.
What needs do be dome to resolve?
Grey smoke from my Yanmar 4jh3te
- Thread starter drtsr1
- Start date
if i am not mistaken it sounds like you are not getting enough fuel to the cylinders..could be clogged fuel filter or clogged up fuel pick up tube in the fuel tank or maybe some air in the fuel line somewhere but usually they wont run if it is air in the fuel line
Interesting. Have not head of that. Others have saiid the injectors need to be rebuilt. Others have said they thought it was the age of the fuel(1 yr old).
Both fuel filters have been replaced and still have the same result. No change
50 gallons of fresh fuel was added to 50 gallons of the old fuel. No change
Both fuel filters have been replaced and still have the same result. No change
50 gallons of fresh fuel was added to 50 gallons of the old fuel. No change
White smoke is steam and bluish is burnt oil but gray and black are definitely fuel related. If the engine is running smooth I would deduce the valve lash is OK. So my mains suspects would be an obstruction in the air intake (perhaps dirty air filter) or a fouled prop. In these diesel engines the throttle is managed by a governor; the fuel is dispersed by the injectors and the volume of air is controlled by the intake valves. Not all the air is instantly consumed by combustion at compression but there is a secondary lingering burn which should take care of any unburned fuel which creates soot. It seems the volume of air may be inadequate for the amount of fuel being dispensed. The engine governor senses loads through the boat's propeller so a fouled propeller by marine growth is usually the cause of overfueling and gray and black smoke. The smoke can be gray now but it could just be the beginning of a worsening situation before it turns into black with loss of power. I would leave the injectors for last. Check the valve lash, replace the air filter and make sure the prop is free of any marine growth.
Thanks for your input.
The engine does not have a air filter, it is turbo charged and only a screen (it has been replaced), the screen was covered with oil prior to replacement.
The prop is clean (new bottom job)
I get the most smoke at an idle or when the turbo is running (higher RPM), in or out of gear.
What is the procedure for checking the valve lash?
Why do you believe it is not the injectors?
The engine does not have a air filter, it is turbo charged and only a screen (it has been replaced), the screen was covered with oil prior to replacement.
The prop is clean (new bottom job)
I get the most smoke at an idle or when the turbo is running (higher RPM), in or out of gear.
What is the procedure for checking the valve lash?
Why do you believe it is not the injectors?
I did not say it could not be the injectors I just suggested you leave those for last due to the complexity and cost of cleaning or replacing. I just mentioned the valve lash as a possibility but if the engine is running smooth and there is no loud tapping noise coming through the valve cover I would not bother with it. Oil in the air intake tube, where did it come from? It could be no coincidence that when the engine is running the turbo at higher RPM is when you most experience the smoking. Locate the source of that oil and you could have found your problem.