Block Heater Alternative to Magnetic
We used a magnetic stick-on heater on an old truck. Later pulled the oil pan and found a crusty ring of burnt oil on the inside. Same thing with a dipstick heater we tried. Stick had a crust form on it. Never liked what we were seeing.
Much better we think is to use a little electric heater installed into the lower radiator hose. Cut a short section out of the hose and install the heater with two new clamps--two on each side for peace of mind. The heater has a little heater element like a tiny household water heater.
Always install the knob on the heater where the 120-vac power cord enters in the downward position.
Have had great luck with these little guys on tractors and trucks, gasoline and diesel. Same on community fire apparatus.
In the hardest cold throw a tarp over the engine and radiator to block wind and let it run continuously if the machine will be needed on a moment's notice. Otherwise two or three hours ahead of use should be enough to take the load off by warming the block.
At 0-F and three hours heating 3- and 4-cyl Kubotas (also White, JD, and Massey over the years) kick off without glow plug lamp showing more than summertime-type 2-3 seconds. No cold-nature smoke. Still need to circulate hydraulic fluid before moving much if possible.
Check local parts houses or Amazon. These little electric radiator hose block heaters run about $40.
If you use one of these water heaters AND an on-board battery trickle charger you can be assured of always being able to get a wintertime start.