One winter when we had a ridiculous cold snap that lasted a couple of weeks, I was on a tour of back-country homesteads, read off-grid. No chance for electric block heaters. So, every evening at shut-down, I lit the Dietz lantern and slid it under the oil pan, then folded the army blanket over a few times and threw it over the still warm engine. The radiator was blocked with cardboard already. Then I unhooked the battery cables and brought it in the house and set it near the stove. Next morning I reversed the procedure and the old 235 fired right up.
Last night of the tour, I was tired and didn't bring the battery in. Wouldn't you know, it went to 30 below. Next morning, no starter action. Even though it was parked on a slight down-grade four of us couldn't budge it. Eventually, the county road crew came by and we threw out a chain. They pulled us about 50 ft. and it was off and running.
Though the deluxe heater worked, I really wished for the recirculating option.
