If you are having problems keeping your Imperial cool and have tried the standard tricks without success, here's a suggestion that helped me on my 413. I tow a trailer and need to have all the help I can get to keep that engine cool. I've done all the standard things - re-cored the radiator, flushed the cooling system, replaced the fan clutch. But I recently found a relatively simple change that gave that engine some real relief. It turns out that there are two standard water pump replacements for a 413. One is listed for non-air-conditioned cars and one for air-conditioned cars. The A/C one has several more impeller blades and moves a lot more water through the radiator. The pumps are the same physical size and interchange exactly. My car has A/C, but somebody (probably me!) put the non-A/C pump in many years ago. With the new, correct pump in, I pulled a 4000-pound trailer over a 2000-foot pass at 86 degrees with the A/C on and never went past the high end of the normal range on the temperature gauge. A marked improvement over the past! If you're having difficulties keeping your engine cool, this might be worth a try. Ken Miller Portland, Oregon 61 and 67 Converts (and a 64 New Yorker Salon)