Bluish smoke- oil or unburnt Fuel?

[jefndeb]

Thanks to all who offered information, i believe, as a general maintenance item, will have the valves checked/adjusted to be safe..
Thanks

 

[C lectric]

I agree with those who say stop running the engine at the dock for the reasons stated.
If you are going to run the engine then actually run it under load for at least 1/2 hr, better longer. and don't just putter around. Get it up to normal cruising speed/revs.

I winterize my boat and it does not get run from Nov untill end of March or APril.
THe engine starts almost immediately. My engine is now 50 yrs old and has about 7,000 hrs.

 

[Mac2]

Another thought on running the engine at the dock. A neighbor at my dock (works at a boatyard) runs his engines once a month for the sole purpose of putting the engine in gear to cycle the water out of the shaft tube. The stainless shaft will start to pit/corrode in water that is depleted of oxygen, so cycling the water is supposed to help with this. Just curious if anyone knows of the timeline a shaft starts to pit.

 

[alfamike]

Blue smoke is always oil.
Black smoke is unburnt fuel
The white smoke looks like steam