Winterising Question

[Sandgrounder]

My new boat, a Trapper 500, will have to stay afloat this winter. It has a Beta diesel with freshwater cooling with a heat exchanger which is cooled with raw water.
When the engine fresh water system has anti-freeze in is there any reason that I cannot simply shut the seacock for the raw water feed and run the engine for a few moments until the exhaust stops producing any water? This would allow me to continue to day sail through the winter while maintaining protection?

 

[Tranona]

No need to do anything. Seawater won't freeze.

 

[Seajet]

Seawater does freeze on the surface, even down here in Chichester if it's a hard winter and especially at places like Chichester & Emsworth Marinas where fresh water flows in, so the OP must decide on the day.

 

[vyv_cox]

The problem with your plan is that the pump is a positive displacement type. Once the seacock is closed the pump cannot rotate harmlessly, as with a centrifugal type, but the vanes will be fluttering and flow will be non existent. A far better plan is to unscrew the face plate of the pump and let any water in it and the hoses run into the bilge. Ideally you should also drain the exhaust trap, which could freeze, bursting it.

 

[Lakesailor]

No need to do anything. Seawater won't freeze.

Windermere is freshwater.

(I realise it doesn't actually say that in the OP)

 

[Sandgrounder]

Apologies; I should have made clear that I sail on a lake

 

[BabaYaga]

A far better plan is to unscrew the face plate of the pump and let any water in it and the hoses run into the bilge.

This will likely not drain the water in the Beta tube stack, at least not all of if. Still potential for frost damage.
I think I would like to run some glycol into the system after each run, to be safe.

 

[VicS]

This will likely not drain the water in the Beta tube stack, at least not all of if. Still potential for frost damage.
I think I would like to run some glycol into the system after each run, to be safe.

Preferably non toxic propylene glycol rather than toxic ethylene glycol in an environmentally sensitive location like a lake unless it can be collected when drained and disposed of safely and responsibly

 

[Mudisox]

I fill up the coarse strainer [with the stop cock shut,] with anti freeze, and give it a whirl, not too long though. Seems ok to me, and no problems even with the sea water around the boat frozen with a thin film.

 

[igytomas]

Running an engine with a seacock closed will damage the raw water impeller, so don't do it.

There should be two drain plugs on the engine to drain the raw water out of the engine (check with Beta manual). One should be on the engine block and one on the heat exchanger. However, what Beta advises is to close the seacock, disconnect the raw water hose, stick it into the bucket with 50/50 mix (water and antifreeze) and run the engine until most of the mix is sucked in. You should see it going out of the exhaust. Stop the engine and reconnect the hose.
This way, the raw water system will be filled as fresh water system.
Some more details you can find here. This is a link to the Beta 20 user manual but for every other Beta engine you will find an on-line manual on the Beta website.

Hope this will help.

 

[Halo]

Often the layer of ice on "the sea" is fresh water on the surface freezing up
Martin

 

[NormanS]

Running an engine with a seacock closed will damage the raw water impeller, so don't do it.

There should be two drain plugs on the engine to drain the raw water out of the engine (check with Beta manual). One should be on the engine block and one on the heat exchanger. However, what Beta advises is to close the seacock, disconnect the raw water hose, stick it into the bucket with 50/50 mix (water and antifreeze) and run the engine until most of the mix is sucked in. You should see it going out of the exhaust. Stop the engine and reconnect the hose.
This way, the raw water system will be filled as fresh water system.
Some more details you can find here. This is a link to the Beta 20 user manual but for every other Beta engine you will find an on-line manual on the Beta website.

Hope this will help.

Oh yeah. I can just see the OP going through all that performance every time he moors up. He wants to continue day sailing during the winter.
What he could possibly do, would be to close the seacock, open the top of the strainer,(assuming there is one), then run the engine very briefly until the water from the exhaust just stops, and no longer. That way the raw water system is empty.

 

[Momac]

Get a mooring with shore power and put some frost protection heat on the boat.