They do use a lot of juice. My last practice was to plug it in an hour before I wanted to start it. The past few years I have not used one very much. All my diesels have good compression now and start pretty well without it down to nearly zero.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.