Raw water cooling and freezing....

[charlumax]

I am trying to plan when I can get the 18' Regal on the water this season. I bought it at the end of last year with diesel 1.7 Dti Mercruiser, winterized and have not yet used it, and is kept on a trailer on my drive...
My Q is, if I use it in say first week in March, then do I have to flush out the raw sea water with fresh, and then drain off the fresh so that it doesn't freeze ?? The dealer says I don't, but perusing Mercruiser manual last night it clearly states if there is any chance of freezing temps then all rawwater must be drained off ??

Any advice anyone??

 

[Boating_Buoys]

It will depend what the likelyhood of very cold weather is in your part of the world... if you are in the depths of Scotland you may need to, but otherwise probably not in March...how oftn do we get a severe, long term freeze then?

If you are keeping it on the trailer at home, if you suspect the temperature is going to drop so low then either quickly drain it off or put a bar heater in.

Hope this helps

 

[Dave_Snelson]

The advantage you have is that you can actually run off the sea water when you get back. This will greatly prelong engine life overall. If you are worried about freezing run a bit of antifreeze into it afterwards. While you are about it, wash the salt off your boat and trailer.

 

[charlumax]

this maybe a stupid question but here goes - i will use hose and muffler on raw water inputs on stern drive to flush out sea water - how do i then get antifreeze in ??

 

[AJW]

Big bucket or bin filled with water/antifreeze mix, dunk leg into it and run for a few minutes or until engine sucks up qty of antifreeze mix. Keep close eye on it so it doesnt run dry! I'dve thought that march wouldn't have been a prob. I used to run outboards all throughout the winter with new probs! (thats the UK winter, not over here in Canada btw)

 

[Roy]

Yep - This is what i did during the winters with my Searay 215 outside my house - flush through the leg with muffs and then dunk it into plastic dustbin filled with a/f and water mix. Perfect every time.

 

[spannerman]

Even easier is what we do when we winterize Mercruisers with Alpha drives, just connect about 3ft of hose to your muffs and place a funnel in the other end and tie it up at the back of the boat to a cleat and pour in the antifreeze mix while the engine is running till it comes out of the exhaust, you will of course need someone in the boat to start and stop the engine.
Alternatively put a small heater in the engine room during the cold spell i.e a 100w bulb or fan heater with a thermostat. Works fine over here in Norway.

 

[charlumax]

do I need to get marine antifreeze or is the local Halfords car stuff sufficient ?

 

[brianrunyard]

I use Halfords, stops freezing and also helps stop corrosion.

 

[Roy]

Halfords or any car stuff is perfectly good enough. By the way, using electrical heat is fine as long as heating does not go off - i.e. power tripped out or grid failure. Best to have the anti freeze in the engine anyway. Why not also put in some cheap heating supply too having wd 40'd all engine area and electricals and when spring comes you have no corrosion, no damp bits, no sticking fuses, no burst engine block, no worries. Turn the key and vrooooom!!!

 

[truebrit]

Run the A/F mixture through a few times to make sure engine is at running temperature and thermostat is open otherwise the only bit that gets "winterised" is the exhaust risers !!

 

[BrendanS]

Depends how environmentally friendly you are. Car antifreeze is ethylene glycol, and is pretty toxic. If you flush this out into the water, then you will potentially kill off a lot of aquatic local life. Ethylene Gylcol is banned in some US marinas for this reason. Polyethylene Glycol is just as effective, but non toxic. Not sure where you'd get it in quantity in the UK though.

 

[bdsweeting]

Just make sure that you don't get caught polluting the water when you relaunch and start the engine thereby blowing the anti-freeze out. /forums/images/graemlins/shocked.gif

Depending where you launch and how observant the locals are /forums/images/graemlins/wink.gif

 

[Roy]

Did not know the difference acshully........ Coinsidering the amount of toxicity that goes into the water these days, I don't imagine the a/f to be a major issue? What the best thing would be then is to flush the legs with the muffs (at home) and let the a/f go down the drain - and into the sea eventually - just like the tens of zillions of cars that have this done every year.