Winterising the Raw water cooling system.

[DaveS]

My boat is now out of the water for the winter, and prior to it being lifted, I drained the engine side of the heat exchanger cooling system, and re-filled it with a 50% mix of antifreeze and de-ionised water.

My intention is now to drain down the raw water side of the system, and leave it empty for the winter.

However, looking at the manual for the engine (Yanmar 4JH3-HTE 100HP), it might not be possible to get at the raw water pump, for which the manual recommends loosening the four cover-plate screws, to let the water drain from within.

The difficulty arises from the fact that the engine is quite a big' lump' in a relatively small space, and the raw water pump lays on the left hand side of the engine (viewed for the rear), and at the bottom of the of the engine. As you can see from the photo, there is virtually no space to get down that side of the engine with a spanner, and be able to see and undo the four cover-plate bolts.

The other raw water drain points I think I can get to, but having to leave water in the pump, is a concern.

I could try and stuff some lagging around the pump, but this really isn't a good option IMO.

Another option would be to take the raw water intake hose off of the 'sea cock', put the end of the hose in a bucket of 50/50 anti-freeze and water mix, then run the engine up to suck it up into the system, and leave it there for the winter.

What do you guys do?

Dave

[BuffaloBill]

Although ours is easy to get at, I mix the antifreeze into a watering can, take the top off the raw water intake filter and then with everything ready at hand, I get Jenny to start the engine on tickover and I keep pouring the antifreeze into the filter for about 30secs and Jenny then turns the engine off and I just ensure the filter is topped up and fit the cap again.

The reason for not undoing things is that we like to use the boat through the winter when conditions allow and this only takes a few minutes each time. Had no problems to date. And as an aside, I do a similar thing to both showers and both toilets.

[Soundings]

Basically, just that Dave. Turn off seacock and suck through a 50/50 water/antifreeze mix. My boat is staying in this year so we just sucked up the antifreeze until it was ejected from the exhaust thus proving it had gotten through the entire raw cooling system. We did use "green" non toxic antifreeze.

[DaveS]

Thanks for your input guys, much appreciated.

I'm going up to the boat tomorrow, and if I can't drain the system down completely, I'll go for the antifreeze solution. Albeit, it will need another trip up to the boat before the really cold weather sets in.

The intake/weed filter is very accessible, so the does seem to be an easy option.

Thanks for the tip on the toilet and shower drain pump system, I will do that as well.

I have already drained down the domestic water system, filled the fuel tank with diesel, and pumped out the holding tank.

Wintersing this boat, which we've only had since August, is a 'new game' for me, as our previous boat (a Viking 24), had an outboard, and the toilet system was a Thetford Cassette.

Dave

[Guest]

it might not be possible to get at the raw water pump, for which the manual recommends loosening the four cover-plate screws, to let the water drain from within.....

....As you can see from the photo, there is virtually no space to get down that side of the engine with a spanner, and be able to see and undo the four cover-plate bolts.

I can't see it clearly in the photo, but if I'm understanding you correctly, I'd concentrate on somehow improving access to the pump.

Aside from needing good emergency access for replacing the rubber impeller, you should really remove the impeller if the boat is being laid up for the Winter, to prevent the vanes from being distorted while squashed in one position.

Is the side wall a bulkhead or the outer hull ? If a bulkhead, could you cut a watertight hatch in it to access the pump from the other side ?

If it's restricted by tanks or other movable objects, I really think it would be worth trying to shuffle things around.

I don't know your boat layout, and my suggestion may seem expensive or overly complex, but if it were my boat I'd really want good access to the raw pump, it's one of the most likely things to suddenly fail....

If it really would be a hopeless task, you could always consider replacing the cover with a "speedseal" , they're designed as an aftermarket replacement for most pump covers in awkward spots. The enable the cover to be removed with only four thumbscrews rather than tools.

http://www.google.co.uk/search?num=10&h ... WuSIeoA9yw

[DaveS]

Indeed, I can see the need to get access to the pump, especially to change the impeller when needed.

The bulkhead to the left of the engine, is the wall of the under-cockpit single berth, which is lined with wall carpeting. The engine side has noise reducing foam attached to it.

An access panel could be cut into this, although it wouldn't be aesthetically pleasing, but if the only alternative is to remove the heat-exchanger tank which sits above the raw water pump, or have to have the engine lifted, then cutting a hole in the bedroom wall might be the sensible option.

My immediate concern, is to get the raw water system drained, of filled with anti-freeze solution, then I can look at other options in the spring.

I need to 'crack-on' with this, as I'm about to start (Monday) a course of hospital treatment, which will require my attending the hospital, every day for seven and half weeks. Although I will get the weekends free, I'm not sure how I will react to the treatment, in terms of feeling much like making the two hour return trip to the boat, plus working on it while I'm there.

The plan for tomorrow, was to drain down the raw water system, if I could, take the fenders off, and cover the canopy with a tarpaulin.

It seems that I might now have to get some antifreeze, and make another trip get this into the system.

Dave

[MBA Marine]

All your replies pretty much take care of the engine, however as your out of the water why not open the seacock and with the engine stop pulled out just turn the engine over to clear whats left in the raw water pump.

back to winterising in general and draining the freshwater system, don't forget to unscrew any drinking water filters if you have any as this is the most common thing i replace after winter.

[DaveS]

I emptied the drinking water filter, when I drained the domestic system Mark, but thanks for thinking of it.

If I'm able to get to the other three raw water drain points, then I could as you suggest, turn the engine over a few times to empty the pump.

I'll see how I get on tomorrow.

Dave

[Guest]

When you do get round to getting better access to the pump, it can be done easily and cheaply with a standard waterproof dinghy bulkhead hatch.

I fitted one in the cockpit of my boat to gain access to the bilge pump oil strainer filter. It needed to be higher than the cockpit floor to have a fall to the hull skin fitting, so had to be behind the cockpit double skin.

I used a 6" Barton dinghy hatch, cost was about £10. The hole was easily cut. the hatch frame sealed with silicon, and i can now open and maintain the Vetus oil strainer easily. The cap on it is about 5" diameter, so even that can be drawn through the hole. I fitted it with a transparent cover, but for your raw pump you could use a standard opaque cover, and even line it neatly with a disc of sound insulating material.

[DaveS]

A nice neat job, and that might be the way to go, when I tackle the issue in the spring.

I had a look today, and the water pump does sit the other side of the bulkhead in single under cockpit berth. Just need to do some measurement, to make sure that I come through the bulkhead, in the right place

I think I'm ok now for winter, as I took the raw water hose that goes pump off at the weed-filter end, and dopped the end down into the bilge, and a fair bit of water came out. The other two drain points, one at the bottom of the heat exchanger, and the other on the geabox cooler, I was able to get at.

I then did as Mark suggested and cranked the engine for a few revolutions, which will hopefully have shifted any water laying in the pump.

Some 50/50 antifreeze and water down into the toilet, and sucked up into the pump, and the same treatment for the shower tray pump.

Fenders off, and stowed in the boat, and the mudweigth brought home for a coat of paint.

So, that should be the boat 'put to bed' for the winter

Dave

[MBA Marine]

You sound well sorted for winter.

The inspection hole business,I think you will need bigger than a round 6" if your looking for access to service the raw water pump, I would go for about 12" square so you have room for both hands to pass through, also with a careful cut you will be able to replace the soundproofing so not to increase the noise through the bulkhead.

Mark

[Guest]

The inspection hole business,I think you will need bigger than a round 6" if your looking for access to service the raw water pump, I would go for about 12" square so you have room for both hands to pass through

I think it would depend on how far away from the bulkhead the face of the Jabsco pump is.

If it's within, say, 5", I would think a 5" circular hole is large enough, as the faceplate of most of them is only about 3" diameter, with 4 or 6 screws on the faceplate.

I'd stay with a round hatch as well, even if you do have to go up to 9". They would weaken the bulkhead far less than a 12" square hole, and the seal (against sound, water, and vapour), would be far more efficient with a circular screw and gasket than a square hatch with latches.

[mbird]

If it's within, say, 5", I would think a 5" circular hole is large enough, as the faceplate of most of them is only about 3" diameter, with 4 or 6 screws on the faceplate.

I think I agree with Mark, and the hatch would need to be bigger than that. You need to be able to get two hands in in order to remove the pump cover screws and not drop the cover itself into the bilge. I'd not want to try to remove an impellor without more room either.

[DaveS]

Thanks for your input guys, its much appeciated.

I now have no doubt, that an access panel is going to be essential, and I will assess just how big it needs to be, in the Spring.

The bulkhead is made of marine ply, which is fibreglassed into the surrounding GRP structure around the perimeter.

On the berth side, it is carpeted, and on the engine side is 25mm foam rubber.

Apart from providing access to the pump, it would also be useful in providing access to the Alternator, should this ever be necessary, especially the bottom mounting bolts.

On the other side of the engine, access to the oil filter is quite easy, as there is a lot more space, and less 'clutter' above it.

Dave

[DaveS]

These might well do the job.

The circular version comes with either an 8" or 10" access, while the rectangular type give a 9" x 10 3/4" access.

Along the length of the berth side of the bulkhead, there is a timber support bar for the bed, and the access point cannot straddle this.

If the point of access to the pump, falls below this, then the access panel/hatch will be nicely out of sight below the bed.

If not, it will have to be on-show above the bed.

Dave

[Guest]

It does sound now as though the biggest practicable access panel would be best, for the items you mentioned.

This photo gives an idea of the fairly small access needed just to change the pump impeller though.

(the face of that brass flange is about 3" diameter)

[mbird]

Nice to see someone using a proper puller rather than a pair of screwdrivers, Strowy! I bought one earlier this year but haven't had call to use it yet!

[Guest]

Nice to see someone using a proper puller rather than a pair of screwdrivers, Strowy! I bought one earlier this year but haven't had call to use it yet!

There's a great temptation for me to be smug and keep quiet, but I'm afraid I lifted that particular photo of an impeller change from google images !!

I do use the skinflint's two screwdriver method, (very carefully though, never levering against the face of the pump flange)

[MBA Marine]

Nice to see someone using a proper puller rather than a pair of screwdrivers, Strowy! I bought one earlier this year but haven't had call to use it yet!

'A pair of screwdrivers'!!!! come on do it properly Point nosed pliers!! : Pullers are best but they can be a bit tricky, once the impeller comes out a little and you can then get the lugs on the puller behind it, it becomes easy. but defiantly a job for two hands.

[MauriceMynah]

Those little round dinghy hatch things... Does anybody know if there,s a cabin floor version, one that could be stood on?

They would be ideal for reaching into the bilgies to clear weed filters.

[ExUserGone]

Screwdrivers every time! It's the operator that does damage not the tools.

[Guest]

Those little round dinghy hatch things... Does anybody know if there,s a cabin floor version, one that could be stood on?

They would be ideal for reaching into the bilges to clear weed filters.

Yes there are, with reinforced lids, like the one I put into my main engine bay hatch.

The main hatch is enormous, and I like to be able to have a quick look-see every time I start (and a sniff - it's a petrol boat ).

This is about the smallest rectangular hatch you can get, but the do do small circular ones. I once had a Hardy which had an ordinary Barton dinghy hatch in the cockpit floor (as an original manufacturer's fitment), and the damn thing kept cracking, so it is important to get a proper "walk on" type.

They come in a wide variety of prices, but this is a case of you get what you pay for. I found the cheaper ones very poorly made, so the one in the photo was £60 !!

[pks1702]

MBM have a couple of video's that might be useful to those that have not winterised before.

Tube heaters in the engine bay, humidifier on and use all winter that's my recipe

[DaveS]

I have a tube-heater fitted in the engine bay, but with that you are reliant on the mains supply.

A power-cut or 'Trip' going out on the 'Shore Power' supply line, and you could be in trouble.

Hence why I have gone for 'winterising' as opposed to using the tube-heater.

Dave

[pks1702]

We have electricity points with easily viewable trips.

It is a daily winter job for Marina staff to wander up the pontoons check twice a day that no trips have occurred.

I want to be able to use our ship at the drop of a hat but understand fully your reasons Dave; best of luck.