I have noticed the temperature on my 1988 240DL spike on occassion to 3/4, especially on cold days. I have replaced the Thermostat twice with NAPA (Part # 157) Thermostats. In the past week I have seen the temperature spike 3 times over 3/4 mark while in stop and go traffic. As soon as I accelerate the temp goes down or, if I idle the car 2500 rpm the temp will drop.

My mechanic claims the fan clutch is fine.

I am pondering buying a thermostat from the Volvo dealer, or a Beck Arnley one from NAPA.

Has anyone had problems with NAPA brand thermostats?

Thanks.

(1) check your coolant level (when was the last time it was changed)

Should be changed every 2 years (50/50 mix) If not sure Change it !!!

ANOTHER THING...Does the engine have alot of gunk on the outside of the block? Caked up oil+dirt will retain heat and make your engine run hotter...CLEANER IS BETTER !!!

(2) Check for leaks (look at the base of the water pump (look for a slow drip while running) If you never replaced the pump it could be getting to be about that time...(Mine lasted 175,000 miles before replacement)

(3) Hoses could be a likely culprit(check for leaks)

(4) Thermostat (I use NAPA) I have had them act up at 100,000 mile intervals (Thats something I can live with)

(5) It could be the circuit board that controls the temp gauge

Your cooling system could be perfectly ok and the gauge could be playing

mind games with your head (I had to replace mine once...actually the dealer had to replace it on their nickle because the 1st. one they put in lasted 1 week and ended up being defective)

(6) Look at the cooling fins on the radiator and if you have a compressor, or a friend that does, blow out any blockage from the backside out towards the grill. (Lower the pressure though so you don't do any damage with the compressed air)

This probably covers most of the stuff...others will probably fill in the gaps. The NAPA part is probably made by a foriegn manufacturer and is

possibly even made by the same supplier for Volvo OEM...but thats just speculation.

Good luck, Jack W.

Engine bay is very, very clean. Coolant is changed annually with distilled water and half coolant mix. All hoses are less then 2 years old and no leaks are noticeable.

Radiator looks relatively new and in good shape.

I'v had the same problem. Last weekend I desided to fix it. Luckly it was only dirt and stuff blocking the front of the radiator. I pulled the radiator and cleaned the dirt out. After that I couldn't get the gauge to rise above 1/2 way, even fully load, 90 degrees and over a mountain pass. Best of luck.