My 82 300SD with 202,000 miles has been running hotter than it should be at highway speeds above 70 MPH. Not at red line but uncomfortably above the 100 degree mark and at 110 degrees ambient was getting close to red line last summer. At slower speeds and idling it does not run above 100.
My mechanic thinks he recalls there was a mfg modification to the water pump pulley in later year models like after 84/85 that replaced the pulley with a smaller one to make it turn faster.
Before I go find a used replacement pulley and new belts has anyone else heard of this and does this sound logical?
The water pump was replaced 2 years ago. The radiator was replaced with a new Behr last week. I just noticed some water/coolant on the driveway that seems to be dripping from the front end of the engine but not at the radiator hose connections. Havent gotten under there to look yet. Thanks!