Cadillac Repair: 94 seville sls 4.6northstar, seville sls, coolant temp


Question
I AM HAVING A PROB. WITH OVERHEATING.I HAVE CHANGED OUT THE WATER PUMP,THERMO,RADIATOR,RADIATOR CAP,CHECKED FOR LEAKS,RAN A BLOCK TEST TWICE PASSED BOTH,CHECKED BOTH OF MY FANS,BOTH WORKING PROP.STILL OVERHEATING AT SPEEDS OF 70-85

Answer
Hi Johnny,

      With all the parts you have replaced you'd think one of them should have fixed your problem. A couple other things to check is the freze point of the coolant. If not around -34 to -50 then it will affect the boiling point and possably lower it. Spray water at low pressure through the condenser from the fan side to make sure there isn't any dirt or restrictions in the fins. Test the accuracy of the coolant temp sensor. It might be actually reading hotter that the coolant really is. I like to use an infra red thermometor and Sears has an inexpensive model.

      The cooling fans on your car are designed to turn on low speed at 223 degrees F and hi speed at 230 degrees F which are maybe higher than you think they should be but are still considered normal operateing range. So maybe you are trying to fix something that isn't bad or that has an out of range sensor.

     Hope that helps. Bill