2 gallons of coolant weighs about 17 pounds and he was 15 pounds under weight. I don't know how much coolant was in his system at the start of the race, but there appeared to be none at the end, because you could see he stopped leaking the last couple laps since no steam was coming out any more. Two more gallons of fuel at the start of the race would have been enough to compensate for losing all your coolant, but nobody could envision the need for doing that. If your cutting it that close, it might be something to consider.