winterizing engine

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Vahevala

Senior Member
Joined
Aug 6, 2012
Messages
100
Location
USA
Vessel Name
Vahevala
Vessel Make
52’ Kristen Custom Flybridge Trawler
Can anyone tell me how important is it to fog a diesel engine during the winterization process? I hired a diesel mechanic to teach me the basics and all went well and I think I now have a handle on all the necessary steps but he asked if I had brought some fogging oil for the inlet manifold. I hadn't and he then said that in most cases from his experience the fogging oil did not enter far into the engine so I should be ok. My engine is a Perkins t6.354.

Prior to this all of my boats were gasoline powered. Being new to the diesel way of life I just want to be absolutely sure I am doing this the right way. It would be easy enough for me to go back and fog the engine. Your input is appreciated.
 
Vahevala,
I sure wonder what your mechanic meant by " he then said that in most cases from his experience the fogging oil did not enter far into the engine so I should be ok" It would seem to me that some fogging oil would go out into the exhaust manifold as the engine is pumping air as the fogging oil is injected into the intake manifold.

I would be concerned the engine would start running on the fogging oil if you injected it while the engine was running. But I've never done it. I asked my best mechanic about it a month ago and he seemed to think it wasn't a very good practice and basically wasn't necessary or perhaps even desirable.

I think I'm going to crank mine for 2 10 seconds and a few minutes later for another 10 seconds. Or thereabouts.

I think I'll go back and read the archives.

Other responses may be interesting on this.
 
As far as I know, there is no "fogging oil" for diesel engines that would not be burned by the engine and possibly cause a run away. If you find one, please let us know.
 
Diesel fuel is inherently "oily" and will leave a film on the cylinder walls, which is all that fogging oil will do.

If you have a compression release on your engine, open it and the throttle and crank for a few seconds to pump more unburned diesel into the cylinders.

If you don't have a compression release then shut the engine down normally after winterizing and don't worry about it.

David
 
Fog intake — diesel engines only

Spray fogging oil into the intake manifold and turn the engine over slowly by hand to draw the oil into the cylinders and spread it. Do not use the starter, even with the stop control pulled out; the engine can start on the fogging oil.

Winterizing Your Engine by Don Casey - BoatTech - BoatUS
 
poker,
Did you leave your wet exhaust hooked up?
 
Diesel fuel is inherently "oily" and will leave a film on the cylinder walls, which is all that fogging oil will do.

If you have a compression release on your engine, open it and the throttle and crank for a few seconds to pump more unburned diesel into the cylinders.

If you don't have a compression release then shut the engine down normally after winterizing and don't worry about it.

David

I agree, I have never fogged a diesel and never seen anyone else do it.:thumb:
 
WE fog , seems to work fine and takes almost no time.

The fueling shutoff stops the engines fuel and the spray can is your throttle IF the engine does run on the fogging oil.

Sealing the intake and exhaust (aluminum foil and duct tape ) is good.

Water , with some antifreez or not in the exhaust or lift muffler is easy to evaporate and feed rust to what ever cylinder is open.

With a 2 stroke Detroit we pull the air box covers and spray fog directly into each cylinder .

Only a PIA the first time when the air box cover gaskets are replaced .
 
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From way up the Northeast where temps get to -30C ( -22F ), I have never fogged. Just lift the intake cock hose and place it into a container of RV antifreeze, run the engine until it comes out the discharge, shut it down and done for the winter.
 
From way up the Northeast where temps get to -30C ( -22F ), I have never fogged. Just lift the intake cock hose and place it into a container of RV antifreeze, run the engine until it comes out the discharge, shut it down and done for the winter.

That is also how I have winterized for 20+ years.
 
Thanks everyone for all of your input/advice. Seems everyone has their way of doing things and now with info from many years experience from all of you I have a much clearer idea on how to proceed. Gotta love trawler forum!
 
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