M12 White smoke exhaust

[rpm]

I have an E28 with the original Universal diesel. I just replaced the injectors and master. She sounds and runs good at all speeds but when starting or when at high rpm it throws a bunch of white smoke. It gets markedly less after 10mins
The power is great, no head gasket problem it seems. Compression is good and she runs very smooth
only 4000 hrs on this rebuilt workhorse.
im thinking condensation in the gas since the boat was barely used since Covid. If so, it doesn’t show in the gas filter to the naked eye.
what is the best way to drain a gas tank?

 

[Stuphoto]

If you stored it with regular or mid grade fuel that may be your issue.
They both contain some alcohol making them burn cleaner, which is great if you are constantly running them and replenishing the fuel.
However it also absorbed water.
The Premium fuels don't usually contain any alcohol or absorb water.
They also don't evaporate as fast, and leave the black tar in your fuel system the cheaper fuels do.

Personally, if it was my boat and it is still running nicely I would just top it off with some premium and run with it.
Bring along a spare filter.

 

[Jerry VB]

I have an E28 with the original Universal diesel. I just replaced the injectors and master. She sounds and runs good at all speeds but when starting or when at high rpm it throws a bunch of white smoke. It gets markedly less after 10mins
The power is great, no head gasket problem it seems. Compression is good and she runs very smooth
only 4000 hrs on this rebuilt workhorse.
im thinking condensation in the gas since the boat was barely used since Covid. If so, it doesn’t show in the gas filter to the naked eye.
what is the best way to drain a gas tank?

Did you have problems that caused you to replace the injectors or was it preventative maintenance?

Since you just replaced the injectors, I would start there (rule #1 of debugging: ask what was changed last before the problem occurred). Are the injectors the correct ones and metered properly?

Ref: Causes of Diesel Engine Smoke - By Color
"White smoke coming from the exhaust usually points to one point of failure: the injectors. Usually, white smoke indicates that the diesel fuel is not burning correctly."

Common Causes of White Smoke:
• Damaged Injectors
• Faulty Injection Timing
• Damaged Crankshaft Keyway
• Damaged Timing Gear
• Low Cylinder Compression
• Damaged Rings or Cylinder Liners
• Water mixed in the Diesel Fuel (Cracked Head Gaskets, Cylinder Head or Block)
• Damaged Fuel Lines
• Low Fuel Pressure to the Fuel Pump
• Damaged or Incorrect Fuel Pump Timing

 

[Christian Williams]

For the record, make sure it's not steam. Steam is most common at starting and high rpms.

Smoke carries a long way. Steam less than 5 feet before it just about disappears.

Yeah, I know, but psychology is a factor: once I start thinking "smoke" it takes a force of will to convince myself it ain't, and I still have to do it every time. In my case steam seems to vary with the dew point, or something, and certainly with load, although my engine temp never exceeds 180.

 

[peaman]

steam seems to vary with the dew point

The closer the air temperature is to the dew point, the longer it will take for the steam to disperse.

 

[gabriel]

Have you been able to smell the smoke? Can you describe the bouquet of smells?

 

[rpm]

Have you been able to smell the smoke? Can you describe the bouquet of smells?

Hello again. I’m running the m12 now. I have been running it everyday for a week. Yes, the exhaust is smoky like a truck in smell, the white smoke lays on the surface of the water then finally evaporates about 10ft out, at water level.
it takes three tries with lots of glow plugs on a cold start ,, that’s the worst part then it finally settles down after 5mins. then runs perfectly,,, I mean perfectly. So I’m inclined to rule out any piston ring problem.

 

[Martyn]

For the record, make sure it's not steam. Steam is most common at starting and high rpms.

Smoke carries a long way. Steam less than 5 feet before it just about disappears.

Yeah, I know, but psychology is a factor: once I start thinking "smoke" it takes a force of will to convince myself it ain't, and I still have to do it every time. In my case steam seems to vary with the dew point, or something, and certainly with load, although my engine temp never exceeds 180.

This seems to be the case with my engine. White "smoke", perhaps steam, wafts out from the exhaust but dissipates within 3 feet. I notice it when running higher RPM's when trying to beat the sunset back to the mooring in light winds.

 

[G Kiba]

Put your hand in the smoke and then feel if it is oil or just water. It is likely steam if it does not have much order or smells of only exhaust. Antifreeze will have a sweet smell. A friend's boat did this for months and then gradually disappeared over time. Still a bit of a mystery but i think it may have been water in the fuel. Not sure but it's gone now. It definitely steam by the touch method.