I have a "new" 1994 150 4.9L 4wd that has an analog temperature gauge. When I'm in 4wd and crawling up a hill the gauge is reading 240 regardless of the outside temperature. The engine has a 195 thermostat and under all other conditions runs under 200, is this normal operating range for this engine or is something starting to fail? pretty simple cooling system the water pump and thermostat should be ok so that leaves fan clutch and radiator.

 

If accurate, no, 240 degF is not normal.

If things are good under other conditions, would focus first on the fan clutch and ensuring the fan shroud is in place, things that ensure max airflow drawn through at low speed.

 

Thanks, for the info I will check out hthe clutch and make sure the problem gets addressed.

 

That 30-year old gauge/transducer combination could be suspect. I'd do some checks around the radiator and such before panicking

 

Everytime I had a fan clutch go bad, the temperature rise was always at its worse when just idling sitting still or in slow stop and go traffic where air flow is most important. Before you condemn the clutch, use a garden hose and make sure your condenser and radiator fins are clear of debris.