Winterising

[Stevie101]

Hi guys

I've not had an inboard engine before only outboards and I was wondering about how to winterise it?
Obviously I will be draining the water system in the cabin and the toilet but we do like to have the odd winter run out if the weather is nice so I was hoping to just put a heater in the engine bay and start it up every couple of weeks.
Is this advisable or is it better to use fogging spray and empty the water out of the engine?
It's 4.3 mercruiser engine

Thanks in advance

[BruceK]

If it's being left on the water (salt) the need to drain the water is not so important as the sea temp never drops below freezing. A old thick duvet over the engine has worked well for me in the past If it's stored on dry land or fresh water the maxim is Dry Air Doesn't Freeze. If it's raw water cooled I'd drain it anyway and flush out with freshwater while doing it. Fogging in my mind is essential. Most wear in boat engines is corrosion related rather than standard wear and tear. Fogging isn't a big job, nor is draining and flushing the system and can be done in an hour after an outing. Remember our winters are not nearly as severe as the USA / country of manufacture. The owners book of words is very conservative and not quite so critical for our climate.

Obviously fresh water systems on board should be emptied and all taps left open including any freshwater toilets and external shower points. Dry bilges is key here if left on the water. Condensate is our biggest bug bear. Stuffs up the electrical contacts, makes the engine corrode and look tatty and produces black mildew everywhere. On my cruiser I leave all the portholes slightly open to encourage air flow and my cover is designed to run water off and has ventilation pockets. Putting in a heater just exacerbates the problems imho. Condensation loves temperature differences.

[Stevie101]

Thanks Bruce,
It will be kept on the canal until spring so fresh water.
Looks like I'm going to have to watch a few you tube vids on winterising then lol

[Ianfs]

I don't think you will need to watch you tube vids about winterising, they can become tedious after a while, as you search for the one which suits you best and they nearly always leave something out. However a lot depends upon its service history and when thing were checked or replaced on the engine and stern drive.
As Bruce has said the other systems should be drained and taps left open.

These things scattered around the boat and in the bilge are a great idea. You can buy them cheaper, this is just an example.

https://www.mailspeedmarine.com/mailspeed-marine-condensation-moisture-trap.html

Although you may not want to do this, your best solution with a raw water cooled engine left in fresh water is to lift her out, run her up and change the engine oil and filter including the fuel strainer (leave the plugs until she is recommissioned in the Spring, then replace them).

Then you have the Stern Drive, when was the last time it was serviced?

If it was within the last year, it should be OK. If you are not sure or it was done a couple of years ago and the boat has had a lot of use, drain and replace the Stern Drive oil and depending upon whether the Impeller was replaced within 2 yrs, you may want to check it.

Having said this, we didn't have a very harsh Winter last year where we lived in West Sussex, it only dropped below freezing for a few days and that was about it. Trouble is, you cannot guarantee this will happen again and as you are oop North, the weather may turn sower at any point and stay like it for a few weeks.

So a lot depends upon how she has been serviced what your weather will be like during this Winter.

If you can answer some questions about the servicing, what sort or hours since the last one etc it may be easier to help more accurately.

[ColinR]

If it's being left on the water (salt) the need to drain the water is not so important as the sea temp never drops below freezing.

Not so sure about that Bruce, ask the Polar Bears I would agree around the UK it is extremely rare that it happens and even then only just.




No pictures but I was down at our marina (Softy South Coast) a few years ago and there was ice around the pontoons. Very rare though and I doubt if, even then, it was cold enough to freeze solid in the enclosed space of an engine.

Fresh water definitely drain and protect. I used some tube heaters in the engine bay with a thermostat to turn them on if the temp got below 4 degrees (that happened to be the lowest setting on the stat). That was for a boat on the top of the dry stack so maximum wind chill.

1963 (I'm old enough to remember this

[betty boop]

Fresh water definitely drain and protect. I used some tube heaters in the engine bay with a thermostat to turn them on if the temp got below 4 degrees (that happened to be the lowest setting on the stat).

how did you manage to get the extension lead up that high? I do have a vision of you cable tie -ing a very long line of many 4 plug lead connected to each other down the side of the dry stack to a nearby office

[ColinR]

Fresh water definitely drain and protect. I used some tube heaters in the engine bay with a thermostat to turn them on if the temp got below 4 degrees (that happened to be the lowest setting on the stat).

how did you manage to get the extension lead up that high? I do have a vision of you cable tie -ing a very long line of many 4 plug lead connected to each other down the side of the dry stack to a nearby office

Th cable dangles down the rack. There are power points all along the base of the rack in groups. The procedure is to coil the cable up on the ground so that it uncoils as the fork lift raises the boat. Can be a pain if is snags I suppose but it works.

No the boat owner doesn't have to climb a ladder to plug it in

[betty boop]

Fresh water definitely drain and protect. I used some tube heaters in the engine bay with a thermostat to turn them on if the temp got below 4 degrees (that happened to be the lowest setting on the stat).

how did you manage to get the extension lead up that high? I do have a vision of you cable tie -ing a very long line of many 4 plug lead connected to each other down the side of the dry stack to a nearby office

Th cable dangles down the rack. There are power points all along the base of the rack in groups. The procedure is to coil the cable up on the ground so that it uncoils as the fork lift raises the boat. Can be a pain if is snags I suppose but it works.

No the boat owner doesn't have to climb a ladder to plug it in

[BruceK]

If it's being left on the water (salt) the need to drain the water is not so important as the sea temp never drops below freezing.

Not so sure about that Bruce, ask the Polar Bears I would agree around the UK it is extremely rare that it happens and even then only just.

The coldest winter on record in 2011 saw a thin sheet of ice in Whitehaven Harbour that lasted a day. In 1962 during the Big Freeze there was ice a mile off the Kent shore. That's it. Sea temps range from 6 -10 deg C over winter in the UK. Never say never but we've had more meteor strikes in the UK than sea freezes. Winterization task 1 - build a concrete boat bunker

[ColinR]

If it's being left on the water (salt) the need to drain the water is not so important as the sea temp never drops below freezing.

Not so sure about that Bruce, ask the Polar Bears I would agree around the UK it is extremely rare that it happens and even then only just.

The coldest winter on record in 2011 saw a thin sheet of ice in Whitehaven Harbour that lasted a day. In 1962 during the Big Freeze there was ice a mile off the Kent shore. That's it. Sea temps range from 6 -10 deg C over winter in the UK. Never say never but we've had more meteor strikes in the UK than sea freezes. Winterization task 1 - build a concrete boat bunker

Odds are in favour of not freezing, I agree. I'd never say never though as the year I tell someone not to bother will be the worst winter for years and they'll end up with a split block and taking me to court for giving them duff advice. It's got to be an individual choice and for the cost of a bit of fogging spray, an anti freeze flush and a bit of time why not do it. It's different also if you keep the boat in the water rather than on a trailer or stack not to mention the fresh vs sea consideration.

Also people who dutifully flush their engines with fresh water every trip are more at risk that those lazy buggers like me who leave the block full of salt (or brackish) water.

Where we are the water up the river is distinctly brackish rather than pure sea so the freezing temp is higher than it would be on a pure salt water berth. It's almost, but not quite, like giving the engine a flush every time we return to the marina.