While motoring today, may engine twice made an odd noise, slowed markedly and let out white smoke, then spontaneously recovered. I checked the Racor to see if there was a lot of water, but no hint of trouble. Any thoughts? P.S. engine is yanmar 3GM
It looks like engine misfiring. One or two cylinders stopped. White smoke is unburnt fuel, most likely.
There are many reasons for such behavior.
Dirty fuel - some particles got through filters and plugged injector temporarily. or
Injectors are getting old or
High pressure fuel pump is acting funny or
Engine is running cold (thermostat isn’t working)
I’d wait until the problem become more permanent.
You may have picked a piece of line on the prop shaft, temporarily overloading the engine.
George
worth changing your injector nozzles, cheaper than rebuild/cleaning and doing it every 3-5 yesrd depending on engine usage seems like a good idea to me
Ron
F32 Newport RI
Sounds like a clogged fuel filter.
Jim Demerest
F36/38 Lady of Remes