Winterising Engine Raw Water Side

Ricd

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Hi...would be grateful for anybodies views on the necessity or not to winterise the raw water side of my Volvo MD2020 with 50% anti-freeze if the boat is remaining in the water over winter. In past years I have done this but have always wondered whether it was really necessary with the boat remaining in the water? Obviously would winterise before lifting out in February.
 
My boat stays in (fresh) water all year round. I treat the raw water side always. Compared to some of the other jobs on the boat it is easy to do and for peace of mind it costs nothing.

HF

I am in the salty stuff:D

It is just its a 200mile drive down to plymouth to do the job and on such a morning as this I really can't get the enthusiasm up.
 
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Not to do so sounds a bit of a gamble. Are you in a marina? If so, what do other boat owners do? Depends upon the local microclimate but the fact that you live so far from the boat would favour Winterising unless you have local marina staff who could be relied upon to do the necessary if a severe cold spell arrived.
 
I looked up seawater temperatures in Plymouth a few weeks ago for another poster. Records going back 10 years showed the lowest recorded to be about 8 C. Temperature inside the boat might be somewhat influenced by low air temperature but I doubt it would be enough to freeze the engine. Does your fresh water system ever freeze?
 
Not to do so sounds a bit of a gamble. Are you in a marina? If so, what do other boat owners do? Depends upon the local microclimate but the fact that you live so far from the boat would favour Winterising unless you have local marina staff who could be relied upon to do the necessary if a severe cold spell arrived.

As i stated, I have winterised for the past 10 years however I have noticed the occasional other boat in the marina running their engine and motoring out throughout Dec to Feb and I think there are still boats racing on Sunday mornings so don't think they winterise every week.
 
I'm in Portsmouth Harbour, so should be a bit cooler than Plymouth. Never have winterised unless boat lifted out (which is a lot cooler). Never had a problem with engine water or fresh since 1994.
 
I looked up seawater temperatures in Plymouth a few weeks ago for another poster. Records going back 10 years showed the lowest recorded to be about 8 C. Temperature inside the boat might be somewhat influenced by low air temperature but I doubt it would be enough to freeze the engine. Does your fresh water system ever freeze?

Fresh water side is 50% antifreeze anyway so never a problem...change it every couple of years.
 
I'm in Portsmouth Harbour, so should be a bit cooler than Plymouth. Never have winterised unless boat lifted out (which is a lot cooler). Never had a problem with engine water or fresh since 1994.

That is roughly how i was thinking...good to know you have experimented with it on my behalf. My feeling is the wetted hull area should effectively warm the boat interior. Agree that on lifting out then winterising is essential.
 
Hi...would be grateful for anybodies views on the necessity or not to winterise the raw water side of my Volvo MD2020 with 50% anti-freeze if the boat is remaining in the water over winter. In past years I have done this but have always wondered whether it was really necessary with the boat remaining in the water? Obviously would winterise before lifting out in February.

If the boat is in the water I don't think it is necessary and I have never bothered. On the other hand, boat out of the water - always do it.
 
I just realised i can check the water temp online. Luckily cardiff bay has a network of sensors, one of which is next to my boat. The water is a chilly 4deg there this morning.
 
The "elephant in the room" is what about the sea water pollution of pumping antifreeze mix straight out in to the marina on start up? It's toxic stuff as I understand it but I cant see how pumping it out can be avoided? Consequently I've never put a/freeze mix in the raw water side of our engine. It has never been a problem either (berthed in Portsmouth and latterly Plymouth).

rob
 
I winterise the raw water system of our MD2030 to stop corrosion in the manifold rather than to prevent freezing. It seems to be worth it as the first flush yields a load of brown gunk.

I leave the water trap full of sea water and to my knowledge this has never frozen.
 
The "elephant in the room" is what about the sea water pollution of pumping antifreeze mix straight out in to the marina on start up? It's toxic stuff as I understand it

Some is, but you can also get a version that isn't. That is what should be used if you're going to be pumping it over the side.

We always used to run KS's engine up ashore before lift-in, to make sure it would start when required (our yard can only lift in at slack water, so being unable to clear the way for the next boat makes you very unpopular!). So that would flush out all the anti-freeze replacing it with fresh water.

Of course, the (possibly toxic) anti-freeze then gets chucked onto the earth and gravel hard-standing, but I'm sure it's had much nastier stuff soaking into it over half a century of use as a yacht yard.

Pete
 
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