First engine winterisation - would you critique my plan?

NormanS said:
I presume you are aware of the other main benefit of using antifreeze, namely it's ability to prevent corrosion.
For all the time it takes to introduce some antifreeze into the raw water side, I and many others will continue to do so. The climate where my boat winters is quite cold, and if I can prevent the chance of freezing in the system, however slight in your eyes, and at the same time help to prevent ongoing corrosion in the manifold and elbow etc, for the sake of 5 litres of antifreeze, I'll continue to do it.
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That's great. I'm not sure why you're getting agitated. All I'm doing is pointing out the science concerning the "freezing". :)

Richard
 
RichardS said:
That's great. I'm not sure why you're getting agitated. All I'm doing is pointing out the science concerning the "freezing". :)

Richard
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I'm really not getting agitated at all, but it would be a shame if someone listened to your advice and then got their engine damaged. My own Volvo MD22 has raw water passing through a cooler in the gearbox, which without breaking into the pipework, has no provision for drainage. Both flow and return are considerably higher than the cooler, so it will always be completely full of water. In temperatures below freezing, and in the absence of antifreeze, it is highly likely that the metal pipes immediately outside the box would freeze. If the water within then froze, it would have no room for expansion. Nuff said.
 
Flushing the raw water had always been my first task once the boat is in the slings and clear of the sea. The yard men seem to expect it so it can't be uncommon. I pour antifreeze into the strainer until it comes out of the exhaust, usually about 5 litres.

I always leave the impeller in place over winter and replace it immediately prior to launch.

I'm not so much concerned about freezing (it's never cold in North Wales, of course), but I flush to try to minimise salt crystallising in the system which eventually could impair flow.

I'm happy to be told that it's not necessary but old habits die hard!
 
I always start by changing the fuel filters ready for next year. An awkward job that creates a mess so I always get them done at the end of the season so mess & smell is out of the way before the next season. Then check the engine still starts & run it for 10 mins to dispell any air in fuel line.
Then I have some plastic tubs which I fill with water . then i disconnect the engine hose from the sea cock & place in the first tub & start the engine. At the same time I stick the end of the shower hose in the tub & start draining the fresh water tanks into the tub. The engine running stops the batteries loosing some storage whilst the pump is running. I run approx 150 litres fresh water through the system so it has a chance to remove a bit of the salt as well. Only then do I add 2-3 litres of antifreeze in the last bit of water.
I remove the impeller.
If I have managed to removed any air locks from the filter change I will know about it by the time I have finished so that is ready to go next year. Then fill the fuel tank to reduce condensation & include a water dispelling additive for the winter.
Whilst engine is hot I change the oil plus oil filter. Every couple of years I remove the sump plug & drain the last bit of oil into the bilge ( it is a GRP tray) & get the last bit of sludge oil out as sucking never gets it all out. It is messy trying to clean up, but that way I know I have clean oil in the engine & only takes half an hour extra.
When the boat is lifted i drain the saildrive & check for water in the oil. I have had to change seals in the past. I also remove the prop for cleaning & anode change
That is about all the engine winterisation one needs to do other than checking pipes for splits, loose connections etc, oiling/greasing throttle cables & not forgetting the cables at the cockpit end. Checking the alternator belt & that connections are not going rusty. Mine did & when a wire snapped the stud broke as i tried to remove the nut to re fix it. It is worth undoing the nuts, oiling & re tightening every year just to know that they can be undone when needed.
I hang the impeller by the front of the engine so i do not forget to re fit it when I re start the engine in the new year.
I then write down what i have done in the log so I remember when I did it & what I did.
 
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I am surprised that no one has mentioned that the first winterisation job is to change the engine oil and filters. Afterwards, run for a few minutes to get the fresh oil coursing through the veins of the engine
 
Daydream, I hope you don't change the oil after the engine has run for the last time. It's important to have good new oil on all the bearing surfaces, not just lying in the sump over the winter.

Re fuel filters, I prefer to change mine in the Spring, in case cold weather over the winter causes waxing in the fuel, and then give the engine a run before launching, to make sure that all is well.
 
NormanS said:
I'm really not getting agitated at all, but it would be a shame if someone listened to your advice and then got their engine damaged. My own Volvo MD22 has raw water passing through a cooler in the gearbox, which without breaking into the pipework, has no provision for drainage. Both flow and return are considerably higher than the cooler, so it will always be completely full of water. In temperatures below freezing, and in the absence of antifreeze, it is highly likely that the metal pipes immediately outside the box would freeze. If the water within then froze, it would have no room for expansion. Nuff said.
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But I haven't given any advice. Tranona gave the advice and I gave the science underlying his advice. :)

Richard
 
scrambledegg said:
Engine is a Sole Mini 33 on a sailboat, indirect freshwater cooled, direct prop shaft, going ashore in Chichester harbour.
I'm most concerned about flushing the raw water circuit, which this time needs to be completed with the boat still in the water. I know this has been covered before in the forum, but still I can imagine it going wrong.
Firstly, is it worth doing this at all? More from the corrosion protection point of view.
The basic plan is to siphon, first water then antifreeze mix, from a bucket with a length of hose into the raw water filter that is part of the sea cock fitting.
With engine running, close raw water inlet seacock, open filter cover, stuff primed siphon hose into the opening, allow maybe 5l fresh water to pass, switch other end of hose to a bucket of antifreeze mix, wait for mix to be seen coming out of exhaust, close filter cover, switch off engine.
What I'm mainly worrying about is ingress of air into the filter opening. If I have low flow from the siphon, or I'm late connecting it, could the circuit get air locked? Could the impeller get damaged?
What happens if the filter is opened without the engine running? Would the raw water in the cooling circuit empty itself into the bilges?
Excuse all these questions. One final one: anyone know where the engine anode on this engine is located? No mention of it in my manual.
Thanks.
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Its highly unlikely that sea water will freeze down there so the main purpose of flushing the raw water circuit is corrosion prevention. I used to do that by flushing with soluble oil solution but I wouldnt dream of trying to do it still in the water. A bucket full of liquid attached by garden hose to the raw water inlet will do the job fine once you are out of the water.

Then:
1/ remove the raw water impellor
2/ change the engine oil and filter
3/ empty the fresh water tank
4/ check the antifreeze in the engine
5/ remove sails and put mouse lines through the mast.
6/ polish hull leaving the polish on the hull
7/ pressure wash the underneath whilst still wet
8/ remove things like liferafts, dinghies etc which re vulnerable to theft
9/ either put the batteries on a battery tender or take them home
10/ spray the engine with WD40 or something similar to inhibit corrosion
11/ remove anchor and chain - take home.

Or better still leave the boat in the water and use it. Winter racing is good fun.
 
NormanS said:
Daydream, I hope you don't change the oil after the engine has run for the last time. It's important to have good new oil on all the bearing surfaces, not just lying in the sump over the winter.

Re fuel filters, I prefer to change mine in the Spring, in case cold weather over the winter causes waxing in the fuel, and then give the engine a run before launching, to make sure that all is well.
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Actually you are correct. i do run it but forgot to say so. As you rightly suggest the point of changing the oil at the end of the season is because of the acid build up in the old oil which will damage the engine over the winter. plus of course put some oil in the bearings etc
 
Like the OP i'm about to antifreeze the raw water for the first time. I've had the engine installer winterise the engine previously but last year the bill doubled to £140!! For adding antifreeze and spraying WD40 ! So this year i'm attempting it myself.

When he's done it previously he put a funnel into the raw water filter and just poured in the antifreeze (with the engine running of course). Slowly but keeping up with the take up.

The one thing I haven't seen mentioned is any particular suggestion for antifreeze. I would have thought that any car type antifreeze would do the job but correct me if I'm wrong. Otherwise it's off to Halfords.

I can't drain the system without disconnecting components so it has to be the antifreeze path. The salt water in it should protect but sod's law says this will be a cold winter.
 
Take the bucket out the cockpit and put it a low as possible as a worn impeller / pump housing may slow the water through to the exhaust and back into the engine compare the size of waterlock to bucket
In theory it shouldn't but it can happen
 
drakes drum said:
Its highly unlikely that sea water will freeze down there so the main purpose of flushing the raw water circuit is corrosion prevention. I used to do that by flushing with soluble oil solution but I wouldnt dream of trying to do it still in the water. A bucket full of liquid attached by garden hose to the raw water inlet will do the job fine once you are out of the water.

Then:
1/ remove the raw water impellor
2/ change the engine oil and filter
3/ empty the fresh water tank
4/ check the antifreeze in the engine
5/ remove sails and put mouse lines through the mast.
6/ polish hull leaving the polish on the hull
7/ pressure wash the underneath whilst still wet
8/ remove things like liferafts, dinghies etc which re vulnerable to theft
9/ either put the batteries on a battery tender or take them home
10/ spray the engine with WD40 or something similar to inhibit corrosion
11/ remove anchor and chain - take home.

Or better still leave the boat in the water and use it. Winter racing is good fun.
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Do you leave the wet exhaust connected to the engine?
This risks condensation in whichever cylinder has the exhaust valve open.
 
Daydream believer said:
Actually you are correct. i do run it but forgot to say so. As you rightly suggest the point of changing the oil at the end of the season is because of the acid build up in the old oil which will damage the engine over the winter. plus of course put some oil in the bearings etc
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But what about the TBN.

Engine oils contain basic ( basic in the chemical sense) additives to neutralise the acids formed. Their concentration is expressed as mg KOH per g of oil and this is the Total base number or TBN which you often hear mentioned.
 
ostell said:
Like the OP i'm about to antifreeze the raw water for the first time.

The one thing I haven't seen mentioned is any particular suggestion for antifreeze. I would have thought that any car type antifreeze would do the job but correct me if I'm wrong.
Click to expand...

For the raw water system the cheapest conventional ( non long life ) ethylene glycol based antifreeze that you can find. Remember EG is toxic to mammals, including pets and children. so store carefully and dispose of responsibly.
 
When I did mine, a couple of weeks ago, I first drained off the coolant from the engine, renewed it, and then used the old stuff to flush through the raw water system.
 
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