Diesel Down Time

[Dave Carlson]

We have been having a discussion here in Florida on what to do if a boat owner goes up north for 3-4 months and their boat sits unused for that time period. The engines are QSC’s and flushed after every use.
The local Marina has a “Boat Watch” which includes a monthly start up of the engines and idle at the dock. My feeling is you will never get 4.5 gallons of oil warm enough to do any good at idle and maybe do actual harm.
Better to leave them sit for 3-4 months. When I lived in Illinois our engines sat through the winter on the hard.

Any thoughts?

Topic

[Rob Schepis]

I agree Dave, unless she’s taken out of the slip and a load is put on the engines to get them up to full operating temperature better off letting them sit. Be sure the seawater is 100% flushed out of the circuit with freshwater or even something like the non-tox winterizing antifreeze that has corrosion inhibitors even though the freeze protection is certainly not needed. And, of course, be sure the engine room air space humidity is regulated. The Boat Watch service would be better off doing something such as checking on an engine room fan and dehumidifier…..

So the boats sit in the water for 3 to 4 months unused. That does bring another issue to mind – crevice corrosion. Stagnant water in cutlass bearings, stuffing boxes, etc becomes oxygen depleted and could lead to crevice corrosion depending on the material properties. Plenty available on Google about this.

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