anti freeze and light bulbs
I agree, use the anti freeze, it's cheap and does the job well. I have used lightbulbs for a lot of stuff, kept a 40 watt bulb in the pump house to keep water from freezing up, and never had a problem, and have used them to defrost frozen engines put a bulb under the engine, then cover everything with a sleeping bag or something (if you can find some old fiberglass window curtains they work great) many engines can handle a freeze without a problem, as long as they are defrosted before starting BUT don't rely on it. light bulbs work to keep machinery ready to go, my lathes and jointer, bandsaws etc all have lightbulbs under them, when I need to use them I turn on that light and a half hour later they are ready to go without having to worry about cold lube or dry bearings (no heat in garage other than a torpedo) put a light on the snowblower, and then put a steel barrel/bucket over it and it's ready to go, working in a cold garage? do the same trick with your tools, light bulb in a bucket and lay your tools out under the bucket, warm tools and you don't freeze your hands, and on a few times when I couldn't avoid it, I've even laid out a tarp, pushed a nonworking truck/car on to it, blocked up the vehicle, wrapped it with the tarp, buried it in snow and put a few lights in there to warm it up enough to change a tranny! But as for protecting a $10k engine? no, I'd say go with the anti freeze and stop any problems cold, if you don't want to use anti freeze, drain it and you'll normally be alright. another great all around heat up tool is a hair dryer, they work better than a heat gun for most jobs, soften sticker for removal, heat up a surface for sticker application, warm your hands, defrost windows, use them to warm the carb on a stubborn lawnmower on a cold day, dry out an area for patching, keep a car warm while working inside it, used to keep one running in the work truck when working out in the snow, always had a warm place to climb into when I got frozen! and if you'e in a hurry to get out the door, you can dry your hair with it Ken.