Winterising engine

Yealm

Yealm

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I’ve got a 5 year old beta 25.
I pay someone to ‘winterise’ it each year- but curious - what exactly does this entail and is it really necessary?
 
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Over here - winters can drop to -25C or lower ..... forgetting to flush through with Anti-Freeze can prove a very expensive mistake.

I don't do all the oil / filter stuff that some do ... I just make sure Anti-Freeze is in the system ... I also throw some in the bilges to stop bilge pumps from being frozen - that destroys them ! ... also into the bog and pump through ..

Water tanks emptied ...
 
From a personal point of view, as there's typically not a vast amount to do and I don't want to be worried every time there's a winter weather warning (living 130 miles from where the vessel is moored at a Solent marina doesn't help!), I do winterise our boat.

On our Yanmar 3 pot I close the raw water inlet, then with the engine ticking over, pour non-toxic antifreeze into the raw water strainer and have an accomplice stop the engine immediately the antifreeze appears in the expelled exhaust. Once that's done, I trap a sheet of heavy guage polythene under the air intake box lid and do similar between the exhaust elbow and the flexible exhaust trunking.

Finally I tie a "tag-out" warning ticket to the main engine battery isolator switch keys essentially stating "Winterised - DO NOT START"

I might have omitted to mention something but think the above is pretty much what's needed - the sole element which can be a real PITA is removing and replacing the rubber exhaust trunking at the steel elbow.

Am I wasting my time? Quite possibly / very likely, given how many years it's been since we've had an extended period of proper sub-freezing conditions on the UK south coast - and I have a small tubular heater attached to a thermostat set to frost protection mode... however, for the modest time involved I'm almost certainly going to do it again in early December.
 
Perkins 4-107 ..... I would have it lifted .. and then close seacock .. open the top of the intake filter sitting on the seacock .. remove gauze filter ... have an old coke bottle that I had cut in half ...
Length of plastic large bore pipe such as drainpipe ... propped up so transom external exhaust exited into the pipe .. other end in a large bucket on the ground ... No need to seal or be fancy ..

Take the half bottle with the screw top ... place into intake filter body .... start engine and pour Anfifreeze into the bottle ... I would put aleast 5litres through .... the exhaust and fluid would basically be directed into the bucket without any back-pressure ... exhaust dissipating .. and antifreeze collected ...

IMHO - just stopping when AF is seen at exhaust is not enough as the AF needs to progressively dilute and push out any water ...

On my Yanmar 2GM ... manual says to open drain cocks on block etc ... let water out. Then close. Remove thermostat and fill engine with Antifreeze through the Antifreeze housing. No mention at all of running engine.
Done as manual said .. all fine and we had -30C last winter.
 
It's not hard to do,certainly for an yanmar 1gm10 like mine,flush,antifreeze and then to finish I stuff an oily rag down air intake and exhaust.not a bad idea to change oil and filter while you're at it,if you've ran the engine for a bit the oil is v easy to extract once warm
 
We always drain and replenish oil and filter too plus all the the above. Marine engines are fighting a loosing battle against salt in the air and whatnot which eventually gets inside the engine.
 
Yealm said:
Connected, dehumidifier, but no heater.
Click to expand...
I put a tube heater near the engine on a thermostat that cuts on when the temperature drops to 5 degrees
I also drain off all the domestic water and have a frost protection heater also on a thermostat near the calorifier. I remove shower heads (or at least make sure they are dry).
I use a dehumidifier. Blocking up air vents with masking tape reduces the energy demand from the dehumidifier.
 
Looking at winterising my two Perkins HT6.354M, the boat will be in the water over the winter connected to shore power. Nothing in the user manual or workshop manual about winterising.

First ascertain if there is antifreeze in the cooling system, if not, most likely, then drain 16litres of cooling water off the engine and replace that with 16litres of antifreeze to give a 50% mixture, cooling system holds 32 litres of coolant for the H - horizontal mounted model, the upright engines have a lower capacity at 30.5 litres

The raw water circuit is a bit more difficult in that there is no mention of how much water it contains, so shut the seacock fill the strainer to the top and then open the seacock to let a little flow back down and then reclose the seacock, refill the strainer to the top and turn over the engine without it starting to pump the coolant around the circuit until I can see it coming out the exhaust so a two person job. I can see why they don't give numbers for the raw water side as there are different configurations on the number of raw water cooled parts: Turbo intercooler, gearbox oil cooler, engine oil cooler, engine heat exchanger, exhaust manifold then out, not all engines have the same amount of coolers and there are different ways the coolers are arranged.
 
Winterising an engine is a good opportunity to, flush out salt water if raw cooled, check the engine anodes, check water pump impellor, actually I leave mine out until the spring refit, change engine oil and in general give the engine a good look over- corrosion, worn drive belts, loose nuts and fittings, condition of engine mounts, any chaffing of cables and hoses etc all those checks which will keep a sweet running engine and prevent future problems. Known thy engine is a good maxim.
 
I've just got back from yard after winterising my Yanmar 2GM ....

First small amount of Antifreeze into raw water filter to clear any seawater from intake hose. Close seacock.

I opened drain cock on side of engine block ... water poured out of engine - so no need unblock anything. Let it drain to bilge (good reason for that ... read later).

Removed thermostat and took funnel and poured in small amount of Antifreeze ... watching drain cock.... saw water then nice blue AF ... close drain cock. Pour in more AF until it ran out of thermostat housing.

Thermostat back in and then to make sure exhaust side and seawater pump was OK ... I should have done this straight after intake hose ... but anyway :

Pour in Antifreeze to fill raw water filter body .... then with stop button out ... hit starter to turn engine and draw that AF through the pump - thermostat bypass and to exhaust. Only needs a half litre or so - just to clear them.
Because Thermostat is cold - the AF will exit via bypass and AF in the block will mostly be still there.

Next is to pump out FW tank and SW lines as they exit via sink outlet and that also has the bilge pump connected ... Best to clear all FW water through ...
Once FW tank is empty ... its bilges time ...
OK - why let water drain to bilge ? Because I want to run AF through the bilge pump .. and I want water there to help get suction ... pour some4 AF into bilge while pump running ... doesn't need much ... half litre is enough.
This will then have AF through pump .. hoses and even the lower sink outlet.

Last is the bog ... half litre of AF into the bog ... pump through various valves / hoses and then out.

Took me about 40mins all told.
 
Just going now to walk from home to the boat to drain off the domestic water due to slightly sub zero temperatures being forecast for a few days starting tonight.
The boat is in the water so not too much to worry about. But better to sort it. I lost a nearly new and not cheap shower head last winter and don't want to repeat that mistake.
 
Next few days - when weathers calmer ... I will be moving my MoBo round to local slipway to winch onto trailer and bring back home for winter ...

That will need Antifreeze through that 6cyl lump ! Its a bit more involved on that, as it has no drain cocks .... two water pumps ....

Will need to have water hose feeding it till engine is warm and Thermostat opened up ... then swap to AF .....
 
Dumping half a tonne of fresh water out the tank is going to take a while, even when it was only about half empty you could feel the difference in the way the boat sat in the water, as the tank is at the stern where the bilge pump is I will have to keep an eye on that in case of water ingress,
 
Definitely DIY if you are able, that way you will have the opportunity to carefully look round the engine to spot any possible leaks etc.

I did mine on the shore yesterday, much as others have said, the main thing is to get AF through the raw water system so that it could not freeze, even if a week or so of minus 10 and also AF is probably causing less corrosion than salt water.

One thing not mentioned is draining down the calorifier, or at least partly emptying it and leaving a hose disconnected so that any ice forming has room to expand, the same also applies to the domestic water pump, and obviously all the domestic water needs to be emptied.

One last easy thing, if ashore open all sea cocks otherwise they can contain a little trapped water, within the ball valve, which if it freezes can be sufficient to split the ball valve - happened to me a couple of years ago !
 
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