1997 Ford Rexhall Overheating: Complete Repair Guide & Troubleshooting Steps

The Quick Answer

Since you've already flushed your 1997 Ford motorhome's radiator and replaced the coolant but the engine is still overheating, common causes include a failing water pump, stuck thermostat, or blocked airflow through the radiator. Ford V10 engines in Class A motorhomes from this era are particularly prone to water pump failure around the 20+ year mark, and the thermostat housing gasket commonly fails on these units. Your next steps should be testing the thermostat operation, checking water pump circulation, and inspecting the radiator fins for blockage from road debris or mud.

What's Causing This

On your 1997 Ford motorhome, several components could be causing persistent overheating even after a coolant flush. The water pump impeller may be corroded or the pump bearings worn, preventing proper coolant circulation through the engine block. This is extremely common on Ford V8s of this vintage, especially if the cooling system wasn't maintained with proper antifreeze mixture ratios over the years.

The thermostat could be stuck closed, preventing coolant flow to the radiator when the engine reaches operating temperature. Ford thermostats typically operate at 180-195°F but can fail by sticking closed, and a stuck-closed thermostat will cause rapid overheating. Additionally, the radiator itself may have internal blockages that flushing couldn't clear, particularly if previous owners used stop-leak products or if the system had significant corrosion buildup.

External factors include blocked radiator fins from road debris, mud, or insect accumulation, poor airflow due to a failed cooling fan or fan clutch, or a blown head gasket allowing combustion gases into the cooling system. Class A motorhomes also struggle with airflow when climbing grades or in stop-and-go traffic, which can reveal marginal cooling system components.

Tools You'll Need

• Infrared thermometer gun ($25-40) for checking temperature variations
• Cooling system pressure tester kit ($30-50) to check for leaks
• Basic hand tools (wrenches, screwdrivers, pliers)
• Garden hose with pressure nozzle for cleaning radiator
• Multimeter ($20-30) for testing fan operation
• Funnel and coolant catch pan
• New thermostat ($15-25, see manufacturer specs for correct temperature rating)
• Thermostat housing gasket ($8-12)
• Fresh coolant (2-3 gallons of 50/50 premix)

WARNING: Old coolant is toxic and must be disposed of properly at a recycling center or auto parts store - never pour down drains or onto the ground.

Step-by-Step Fix

WARNING: Always work on cooling system components when the engine is completely cold to avoid serious burns from hot coolant and components.

1. Start with the engine cold and remove the radiator cap. Look for signs of oil contamination, rust particles, or unusual bubbling when the engine runs, which indicates head gasket issues or internal corrosion.
2. Test thermostat operation by starting the engine and monitoring the upper radiator hose temperature with an infrared thermometer. The hose should stay cool until the engine reaches the thermostat's rated temperature, then quickly become hot as the thermostat opens. If it stays cool or becomes hot immediately, replace the thermostat.
3. Check water pump operation by observing coolant flow in the radiator with the cap removed while the engine idles at operating temperature. You should see steady circulation. Look for signs of leakage around the water pump housing or listen for bearing noise, which indicates water pump failure requiring professional replacement (4-6 hours labor, $200-400 parts).
4. Inspect radiator airflow by cleaning all debris from the radiator fins using compressed air or a garden hose from behind the radiator. Pay special attention to the area between the radiator and air conditioning condenser, where debris commonly accumulates.
5. Test the cooling fan operation by letting the engine reach operating temperature. The fan should engage automatically, and you can test the fan clutch by spinning it when cold - it should have noticeable resistance when cold but turn more freely when hot.
6. Perform a cooling system pressure test to the pressure rating shown on your radiator cap (typically 15-16 PSI) to identify any external leaks. Hold pressure for 15 minutes - any pressure drop indicates leaks that need repair before other components will function properly.

When to Call a Pro

WARNING: Call a professional immediately if you see white smoke from the exhaust, milky oil on the dipstick, or coolant bubbling excessively in the radiator with the cap off - these indicate head gasket failure, which can cost $2,000-4,000 to repair on a Class A motorhome. Also seek professional help if the cooling system won't hold pressure during testing, as this requires tracking down potentially hidden leaks.

Water pump replacement on your 1997 Ford motorhome typically requires removing the radiator and fan shroud, making it a 4-6 hour job best left to professionals unless you have significant mechanical experience. The labor cost runs $300-500 plus parts ($150-250 for the pump). If multiple components need replacement simultaneously (thermostat, water pump, radiator), a shop can often provide package pricing that saves money over individual repairs.

WARNING: Consider professional diagnosis if you're uncomfortable with electrical testing of fans and sensors, or if the overheating persists after replacing the thermostat and cleaning the radiator. Cooling system problems can quickly cause expensive engine damage, so don't continue driving if temperatures exceed 220°F or if you see any of the warning signs mentioned above.