Also engine could be flooding/over primed if the box fails to turn it over.
I made a crude engine pre-heater using a small sweetcorn tin (lol), a 12v H7 car bulb mounted through a hole made in the top of the tin connected to some wire/crocodile clips from an old car battery charger, within 3-4 mins it heats the engine to the point at which i can't touch it. See thread:
http://www.oople.com/forums/showthre...645#post508645
I used it whilst running in a new engine recently & it never failed to start on the 1st attempt, just an idea
