PeachParts Mercedes-Benz Forum - View Single Post - Mercedes 126 -V8 -What temp is Overheat?

G-Benz · #9 01-11-2002, 12:56 PM

Do you have the correct pressure cap and if so, is it absolutely tight?

I would experience high temps whenever I fired up the A/C and eventually found out that the system wasn't able to hold sufficient pressure, thus, higher temps. I later found that DUH, the cap wasn't on tight!

Are your radiator hoses collapsed after the engine cools? Again, if the cap isn't on securely, that may be the case.

I've read that the aux fan sensors are designed to kick the fans on at 117C, not 110.

You have an A/C condensor located directly in front of the radiator, so when the A/C is on, the condensor disperses heat with of course, is absorbed by the radiator behind it (hence, higher temps). That is why you have the aux fans, to compensate for the added heat being dispersed by the A/C system. If your aux fan temp sensor is not functioning properly, the fans may not come on at all! Mine is located on top of the coolant pump near the thermostat...