View Full Version : Winterizing

Walter Parelli
08-02-2002, 08:33 AM
" Any thoughts out there on winterizing a raw-water cooled engine via antifreeze instead of draining?

I've always drained engines at season end, and never had a problem, but recently heard advice that, given the angle of the engine mounting, some pockets of water may not drain fully from an engine. (Admittedly, remembering and finding all of the drains and removing hoses is time consuming and risky itself.) The advice went on to say that the only completely sure way to avoid catastrophic internal freezing is to hook up a hose to the cooling water pick-up pump, and draw in a solution of antifreeze from a bucket. The engine is raw-water cooled (1965 Chris Craft 431 Lincoln), but runs only in fresh water, so salt corrosion should not be an issue.

How would one know when the engine has "enough" antifreeze in it to prevent freezing - when the engine kicks the solution out of the exhaust, or is there some other trick? About how many gallons of solution is needed for this operation? This sounds like it ought to be relatively simple, but I've never done it, and the stakes are high! Thanks in advance. "

08-02-2002, 09:08 AM
" The practice around here is to just take the raw water hose and put it in a bucket of straight, non-toxic anti-freeze and run the engine until it comes out the exhaust and then fog the engine while it is still pumping anti-freeze. Seems to work fine.

Use the grade of anti-freeze appropriate for your coldest temperatures and be conservative as there will be some mixing unless you run a lot of this stuff through the engine.

I use the drain down system myself on my fresh water cooled Crusaders. Works fine. The only problem I had with this method was forgetting to drain the oil cooler on a raw water cooled Mercruiser. "

pat carnahan
08-10-2002, 05:04 PM
" If the engine is not hot the thermostat will trap the water in the block and it will freeze. Even when the antifreeze comes out the exhaust. On some older engs not sure about the lincolns they ran water thru the intake manifold, these engines had a large pipe plug in the top of the intake manifold you had to pull that plug and pump out the water. Your best bet may be to hunt down your drains. If you want to pull the drains and then dump antifreeze down the hoses going to the thermostat housing until it comes out your drains then install drain and add more for good luck. Do the same with the exhaust manifolds. Another way is to drain the block and manifolds then start eng with antifreeze and count on flushing anything you didnt drain, but I would redrain block and exhaust after first attempt to be sure you got it right. And look close at that intake manifold for that large pipe plug. "

rob jared
08-13-2002, 09:35 AM
" I drain the block and hoses (including heater) as best as I can (yes, it is a bit messy, and there are lots of drain points) and then I add RV or plumbers antifreeze to catch the water pockets you mentioned. I have done this every year since 1991 on a couple of different ski boats (Ford & GM motors)and have never had a problem. I live in Northern Alberta, and we always see -40 degrees F each year, never had a problem. I don't use regular automotive antifreeze for the same reason I put it in - you will never get it out completely until you are at the lake, and you don't want to dump that stuff in the water.