Winterizing 23D diesel engine

[Seachelle]

Hi, folks!

This will be the first time we've had to winterize the diesel engine aboard SV No Mas, our 1990 Com-Pac 23D. We have a 1GM10 model. We've been 'YouTubing' it to try to find videos of the procedure, but I thought I'd reach out, here, on the forum to see if anyone might be willing to share experiences of the process. I'd be so grateful for your tips and advice!

Thank you!
~ Chelle
SV Sunflower (Sunny) | 2021 Com-Pac Legacy
SV No Mas! | 1990 Com-Pac 23D MK3
https://passagesfromtheheart.wordpress.com

[moonlight]

Is it freshwater cooled (antifreeze w/ heat exchanger), or raw water cooled?  Critical differences.
Clearly all raw, natural water needs to be purged; either by blowing out or by pumping in RV antifreeze.  A hose in a bucket led to the seawater pump does that.
Are you storing inside, or outside?  If I recall, you're WAY up north.  so if in a warmish barn it's different than outside in -20.
A worklight, incandescent bulb, in the engine bay doesn't hurt either.

And don't forget the freshwater system on board, the head if so equipped, et cetera.

[Andre]

I'm no expert on this, only having an air-cooled outboard, but are you sure about using RV antifreeze? That would be appropriate for potable water systems but I would think an engine antifreeze would be called for here.

Andre

[Cpy23ecl]

You don't want to use automotive antifreeze for raw water cooled engines or on the raw water side of fresh water cooled engines as automotive antifreeze is toxic and you don't want it flushed into the lake when starting the engine in the spring.

I've always used rv antifreeze on all my inboard boat engines for decades.

Fred

[Andre]

Right, got it, duh ....

I was thinking corrosion protection but on the raw water open loop side I guess that's kind of meaningless.

Andre

[bruce]

Just to be clear, while propylene glycol used in RV antifreeze formulations is less toxic than the ethylene glycol typically used in cars, both are toxic to aquatic life, as are other additives for corrosion. Neither should be discharged fresh or salt water.
https://www2.illinois.gov/dnr/cmp/Documents/TipSheets.pdf

[Mas]

Hey Chelle, just noticed you post about winterizing the diesel on No Mas. Assume your done with it by now? Sorry I wasn't too helpful on this.
I actually am aboard Interlude and just finished her winterization. Same process just more pink stuff needed!