I'll start by saying I have a 190 thermastat with a stock fan and radiator which looks very clean and a new water pump. When I am driving normal the temp stays at about the 190 mark, but if i'm doing alot of romping the temp will go up to about the 220 range. It seems to take a long time to get back down to normal temp. What is a safe temp to operate at? I don't know if I should get a cooler thermastat or a better radiator. As always I appreciate your advice.

 

are you running on an aftermarket gauge so you are certain of the temp range? you should be running a 180 t-stat but 190 is fine too, but 220 is getting a bit on the high side.

could be a blockage in your cooling system. have you seen any sludge build up and flushed it at all? does it ever overheat sitting still or only when you get on it?

 

I do have a aftermarket gage. I just had the radiator off not that long ago when I replaced the water pump. The radiator looked very clean, no sludge build up at all. If I run it with the cap off the water appears to be circulating fine. If I just let it idle it will get around the 200 mark.

 

is the fan clutch new? did you actually flush the rad out when you had it off? did you replace the rad cap?

 

I flushed out the radiator but I did not replace the fan clutch or the cap. I had just got the car and the water pump gasket was leaking. The water pump looked like it might be the original so I replaced it. How would I know if the clutch or cap are bad?

 

i would just replace the cap. its like 5 bucks. i'll be honest, someone else would need to chime in on that, i dont know if there is a test but i know its based on a spring pressure of 15-16lbs of pressure. sometimes they go bad and it makes your cooling system do all kind of crazy things.

as for your fan clutch. try spinning it by hand its it relatively easy or difficult to do?