anti freeze in the raw water system.

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ianainge

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im going to attempt to winterize the engines next week and put anti freeze in the raw water system. ive been told to put end of hose that goes to pump in a bucket of anti freeze, turn over the engine until all the contects are sucked up.

question is how much anti freeze will be needed, i.e how many bucket fulls, to fill the system 200 hp volvo ad41, and i read somewhere that i should drain the exhaust manifolds of salt water is this correct and how do i do it.Any thing else i should do or be aware of ?
 
Best check the owners manual. You should have a sort of bleed screws on the underside of them somewhere. The average builders buckets hold 2 gallons, how much do you want in there!

Yeah! I know its running rough, but your lucky its running at all!!
 
I put 50/50 mix in as you say and run engine until exhaust water changes to colour of the antifreeze used
 
If your engines have a thermostat on the raw water side then make sure they are open (i.e engine up to temperature) before you introduce the antifreeze.

Also remember that some antifreeze (ethylene glycol) is poisonous - just remember the Austrian wine fiasco a few years ago, so be careful what you do with any overspill.

I was considering making up some form of tank, fill with antifreeze then drop the leg into this to rinse through the cooling system and catch any overspill. This would allow me to continue using my trailered boat up until the end of the year without fear of freezing. Alternative would be to install some kind of frost-stat controlled heater in the engine compartment.

Has anyone tried either of the above?
 
You don't need to FILL the system with antifreeze, the little places where water will lie inside the block, just need to be antifreeze, 10 gals should do it nicely. Mix as you would for a car or boat fresh water system, I always went a little more. I would also mix some soluble oil, (from a machine shop, as cutting fluid) to your mix, this will coat all internal parts with a film of oil, which will protect everything! If you pump this mixture through the engine, you won't need to drain the manifolds, I've used this mixture professionally for years on a lot of engines and it works a treat, it wont attack your hoses either!
 
I've found it is difficult to remove the inlet hose on 41s and get into a bucket, so I pour 50/50 anti-freeze mix in through the raw water strainer. I remove the impellors and use a funnel with a lenth of hose, the hose being pushed into the outlet of the strainer housing. I keep pouring until the colour of the water coming out of the exhaust is a nice blue (assuming you are using blue anti-freeze). It takes about 2 gallons. Then run some back through the inlet to flush that side of the system.
 
Excellent idea, would do the job nicely, but you could also leave the impellor in and just pour it in with the engine ticking over, then you're sure it has got into every nook and cranny. With inlets through the legs, we just had one of those natty earmuff type thingies, with a pipe into a tap on a 20 litre container held up in the air, or balanced on the swimming platform. No swimming platform, I used to reverse the old rangy back and put it on the roof!
 
You can't leave the raw water strainer top off, with engine running, as it's on the pressure side of impellor. Water everywhere (except engine) if you do.

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I've never heard of that before, must be peculiar to wolwos' why would you want to strain it after the pump, that allows bits to destroy the pump impellor??? Come to think of it I've seen that on the wolwos still baffles me.
 
Tis true, pump is mounted on end of injection pump, water feeds along port side of engine, up to pump. Filter is mounted on top of pump on outlet side. Agree it is a bit daft.

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Thats not the only strange arrangement!
On my AQD32's, the raw water comes up thru the leg and then thru the oil cooler before reaching the pump and thence on to heat exchanger. No filter at all unless you call the oil cooler tubes stack a filter! Got all the bits now to fit weed filters pre oil coolers but not exactly an easy job to fit in space available......

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Hi people. I'm quite new to boats and eager to learn. I must admit that I hadn't considered it neccessary to treat my raw water system. Are we talking 'raw fresh water' here? Is treatment still required when the raw water is salt? I always thought that the freezing temperature for saline water was lower than we could expect here in the UK. I am happy to be educated on this one!

CLP
 
The antifreeze mixture for the sea water side is for corrosion protection, not really to stop freezing, thats why I reccommend adding soluble oil to the mixture.
 
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