insulating your engine

Mark M

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28 Oct 2009
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Hi I have a twin engine deisel inboards, on my boat which is moored in the river all over winter, and will be winterizing my boat on the Thames soon, and was wondering as an additional measure, I was thinking of packing rockwool insulation around the engines as a backup to stop them freezing, has anyone done this or do you think it may cause more condensation i in the engines, which might do more harm than good,maybe i am just being over causous
 
Make sure the antifreeze in the inner cooling circuit is up to strength as a first step.

When leaving the boat you need to flush the raw water side through with a strong antifreeze mixture until you see it coming out of the exhaust. How you do this will depend on the configuration of your raw water inlet side - on my boat I have a large weed filter immediately above the sea cock and the top of the filter is conveniently above the water line. So, with the engine running I take the top off the weed filter, close the seacock and pour the antifreeze mix into the top of the filter housing and get someone to give me a shout when they see the green stuff coming out at the exhaust. Shut the engine off and thats it.

Bear in mind that the temperature of the water under the hull is a few degrees warmer than at the surface so, unless its a really severe freeze it will probably never drop below zero and will act as a mild radiator up through the bottom keeping the engine compartment warmer than the outside air. Over the last several years I have kept a max/min thermometer in the engine bay and it has never gone below zero.

I dont use engine bay heating or dehumidifiers at all. The best place for the insulation is under the engine hatches so that warmer air is kept in.
 
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Not sure it ever gets cold enough these days, especialy if you leave the boat in the water. All i've done for at least the last 15 years at least is plaster the engines in WD40 or similar and a couple of blankets to keep the damp off and some degree of frost protection. Anti freeze in the closed circuit side obviously, I also take the boat out for run every couple of weeks.
 
Thanks

Cheers Chris & Boatone

The antifreeze i will be doing anyway, ny boat is a Birchwood 33 so there is no problem flushing it throught the system, so a bit of insulation in the form of a few blankets should be a good back up as well

Cheers again

Mark
 
Cheers Chris & Boatone

The antifreeze i will be doing anyway, ny boat is a Birchwood 33 so there is no problem flushing it throught the system, so a bit of insulation in the form of a few blankets should be a good back up as well

Cheers again

Mark

Ah! A proper boat!

Makes a nice change from all those Brooms and tin things!

Where abouts are you on the river?
 
We just stick a tube heater in the engine bay on a thermostatic switch. Comes on when it needs too and keeps the chill off the engine bay.

Having said that we do use our boat every weekend (even through the winter) so "winterising" it as some do would mean a hell of a lot of work every weekend just to take her out for a coupe of hours.
 
In Ontario Canada they shink wrap the boats and have a bubbler over the stern to keep the ice from forming. The engines are of course winterised and have a sump heater.
 
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