A hot running Delorean can be caused by several things. The otterstadt switch only controls the temp at which the fans start and stop if the A/C is not running. Get an infra-red temp sensor or just a plain old thermometer and actually measure the temp of the coolant. Make sure the anti-freeze (aka coolant) is not old, is a nice color, and is not acidic. The thermostat can be sticking. You can test it in a pot of water on a stove or just replace it. Bleed the radiator of all air. Make sure it is not clogged with debris on the outside. Make sure both fans run, run in the right direction, and the fans are not loose on the shafts. Make sure the front grill is not blocked with anything like a plastic bag or a license plate. If the hoses and belts are old they should be replaced. I also suggest you get a new, metal radiator and a metal header bottle. Get the uprated circuit breakers for the fans and at least have the fan fail bypass jumpers NOT THE BLUE FAN FAIL RELAY! Pressure test to 15 psi for 15 min. If you do all this you should have a bulletproof cooling system. If you have to add coolant once the system is bled you have leaks which MUST be repaired. Coolant is not "consumed". It is recirculated and if the level gets too low some of it is getting out. Eventually enough will get out to let air in. Once that happens and the system gets airbound you will overheat the motor. This is why leaks of any magnitude cannot be allowed. David Teitelbaum vin 10757 --- In dmcnews@xxxxxxxxxxxxxxx, mike.griese@xxxx wrote: > 220 is not overheating, although it seems a little high. If your > system can hold 15 lbs pressure for any length of time, your > boiling point is closer to 250 degrees. > > The thermostat does not control the fans - the otterstat does. That's > the switch in the coolant pipe on the left-hand side of the engine b To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/