Whoa! If you are running pure coolant (which is usually just another word meaning Anti-Freeze, by the way), something is goofy here. You should be running a 50% or lower solution with water. Over 50% is a mistake, as the effect of raising the boiling point reverses, and also the solution becomes a much poorer heat conductor, and is too viscous in the bargain. If a competent mechanic filled your system, you are probably all right, but at least take it to a radiator shop and have him use his tester to tell you what mix you have. If someone has put the new snake-oyl type non-antifreeze "coolant" that some unscrupulous vendors are touting as a new "scientific elixir" in your car, this may be your whole problem. If it were my car, I'd drain the radiator, block and heaters, then flush with clean pure water, and refill with a 30% solution of ethylene glycol anti-freeze (the common green stuff) and 70% water, and see if that doesn't help your problem. Adding a coolant recovery system has no effect at all on the operating temperature of your car, it merely catches any overflow and returns it to the cooling system during cool-down. If you've noticed a difference, it must be because it is now keeping your radiator full of fluid, whereas previously, you must have been driving with a less than adequate fill level. As long as the fins are covered in the top tank with the engine cold, your system will be cooling as well as it can. As far as cleaning out your system properly, as we said previously, directions for this process are in the IML archives (I know, I wrote part of them!). Dick Benjamin ----- Original Message ----- From: <Imperial59crown@xxxxxxx> > Today I went and bought an overflow canister, and installed it in all of five > minutes. It seemed to do the trick, since I took her out for a long drive, > both city and freeway, and the temperature stayed right around 190 degrees, > climbing to 200 during long stop lights, but then returning to 190 when > rolling again. I would like to clean out the system, but have no idea how to > do this. The radiator was flushed when I originally had the car in for > servicing, but I doubt the lines through the engine were routed out. I'm > pretty sure the radiator is running with pure coolant, and no water, and > since I live in Southern California there is really no need for antifreeze. > Would it be beneficial to add water? Many of the coolants say right on the > label, do not add water. > Bill '59 Crown > Dick Benjamin