92 e150 convertion van

Can the air get through the radiator? Take a flashlight and have someone hold it behind the radiator between the fan blades. (you may want to shut it off first). Then stand back a few paces, you should be able to see that light through the radiator AND condenser. If not, you need a disassembly and cleaning of the exterior of these items. A pressure washer can help, but be careful not to bend the fins on either item. You may have to remove the grill, to get a good straight shot.

"biker" wrote: (1992 E150 Van Conversion 302CI with trans cooler)

I pull a pop up trailer and whenever the weather is very HOT & very HUMID the motor overheats. I have cleaned out the radiator, flushed & changed the fluids, changed the thermostat, put a new fan clutch in, changed the radiator cap, and checked to make sure the fluids are moving when running. But it still overheats only when it very hot & humid out. The 80's are fine, 90's it overheats. What am i missing, HELP? ________________________________________________________

Humidity is not the problem - heat exchangers (radiators) work better in humid conditions than in dry conditions.

Some possible solutions:

Remove the radiator and have it boiled out by a radiator shop to remove deposits that won't respond to retail flush chemicals.

Buy a new radiator with an extra row of core tubes.

Replace the fan clutch with a fixed spacer.

Use a hose to flush the dirt out of the radiator fins, and the AC condenser fins if so equiped.

Be sure insulation pads in the engine compartment do not restrict air flow.

Do not use 100 per cent coolant in the radiator. A 50/50 mixture of coolant and water transfers heat more efficiently.

Replace the water pump if needed.

Good luck.

Rodan.