when you do start it up the oil will be thick and the pistons will be un-lubed for a while. usually at any start up the cylinders are dry anyway so that is more or less normal.
mobil 1 syn 0 wt oil is what i have now in both red and brownie. both are plugged in. i will go out in a few minutes and see if they start at -7f.
so where are you in wisc?
addendum from
www.dieselgiant.com
A cold engine does not start at its best! Don't wait till it gets cold to install this high powered block and coolant heater. Heats the engine and cooling system to nearly 100 degrees for a quick start-up on those cold mornings. Made of a heavy duty element and electrically grounded for safety. Those cars running on WVO or Veggie really need a good block heater to reduce the time you have to run on petroleum. A warm engine reduces wear on rings and valve train components. Also a reduction in start-up emissions with a warm engine will result. Reduce smoke and decrease the time it takes to achieve full oil pressure at idle. Great for engines with high miles or lower than normal compression. Helps them start MUCH more quickly and reduces glow plug system and battery wear
addendum from me
red started right up.
brownie with the suspect block heater is quiet. her glow was very long compared to reds. obviously the diff between the hot and cold engine. back to the charcoal briquets in the cast iron frying pan.