Radiator Hose - Upper

Remove and replace the upper radiator hose on a 1972 Ford F-100 with 302ci V8 engine, including coolant drain and refill.

Warnings

Tools required

Parts

• Upper radiator hose × 1 — Use OEM specification for 302 V8
• Hose clamps (worm gear type) × 2 — 1.25-1.75 inch range

Fluids

• Ethylene glycol green 50/50 — 2 qt

Preparation

1. Ensure engine is completely cold to the touch
2. Park vehicle on level surface and engage parking brake
3. Place drain pan under the radiator drain petcock on the passenger side bottom of the radiator
4. Have replacement hose and clamps ready for installation

Procedure

1. 1

   Drain coolant from radiator
   Open the radiator drain petcock at the bottom passenger side of the radiator by turning counterclockwise. Allow approximately 3-5 quarts of coolant to drain into the pan until the level drops below the upper radiator hose connection. Close the petcock when finished.
2. 2

   Remove radiator cap
   With the system depressurized and cool, remove the radiator cap to allow air into the system and ensure complete drainage from the upper hose area.
3. 3

   Loosen radiator-side hose clamp
   Locate the worm gear hose clamp securing the upper hose to the radiator inlet neck. Use a flathead screwdriver to loosen the clamp screw by turning counterclockwise approximately 5-6 full turns. Slide the clamp down the hose away from the radiator connection.
4. 4

   Loosen thermostat housing hose clamp
   Locate the worm gear clamp at the thermostat housing on the front of the intake manifold. Loosen the clamp screw counterclockwise 5-6 full turns and slide the clamp down the hose away from the thermostat housing neck.
5. 5

   Remove upper radiator hose
   Twist the hose back and forth while pulling to break the seal at both the radiator and thermostat housing connections. If the hose is stuck due to age, carefully use a hose pick or flathead screwdriver to pry between the hose and fitting without damaging the metal necks. Remove the hose completely and allow any remaining coolant to drain into the pan.
6. 6

   Clean connection surfaces
   Use a shop rag to clean the radiator inlet neck and thermostat housing outlet neck. Remove any old rubber residue, corrosion, or debris. Inspect both necks for cracks, corrosion pitting, or damage that could cause leaks.
7. 7

   Install new hose clamps
   Slide the two new worm gear clamps onto the new upper radiator hose before installation. Position one clamp approximately 2 inches from each end of the hose with the screw mechanisms accessible from the top or front of the engine for easy tightening.
8. 8

   Install hose onto thermostat housing
   Push the lower end of the new upper radiator hose firmly onto the thermostat housing outlet neck until the hose is seated completely against the base of the neck. The hose should cover approximately 1.5-2 inches of the neck. Slide the clamp into position over the connection point, approximately 0.5 inch back from the end of the neck.
9. 9

   Install hose onto radiator
   Route the hose to the radiator inlet on the driver side top tank. Push the hose firmly onto the radiator neck until fully seated. Ensure the hose routing does not kink or contact sharp edges, the fan, or fan shroud. Slide the clamp into position over the connection point, approximately 0.5 inch back from the end of the neck.
10. 10

    Tighten hose clamps
    Tighten both worm gear clamps by turning the screws clockwise with a flathead screwdriver. Tighten until snug and the hose cannot be twisted by hand, but do not overtighten as this can cut into the hose. The clamp band should indent the hose slightly but not cut through the outer layer.
11. 11

    Refill cooling system
    Using a funnel, pour premixed 50/50 ethylene glycol green coolant into the radiator until it reaches the base of the filler neck. Pour slowly to allow air to escape. Add coolant until the radiator is full to the base of the filler neck (approximately 6-8 quarts to replace what was drained), then start the engine and continue adding as the level drops during burping. Verified detail (2 quarts is insufficient for initial fill. If 3-5 quarts drained from the radiator and hose, approximately 3-5 quarts should be added initially before starting the engine to avoid running dry.): Using a funnel, pour premixed 50/50 ethylene glycol green coolant into the radiator until it reaches the base of the filler neck. Pour slowly to allow air to escape. Add approximately 3-4 quarts initially, then start the engine and continue adding as the level drops during burping.
12. 12

    Burp cooling system
    With the radiator cap off, start the engine and allow it to reach operating temperature (thermostat opens at approximately 180-195°F). Watch for coolant circulation in the radiator and add coolant as needed to maintain level. Allow the engine to run for 5 minutes after the thermostat opens to purge air from the system. The heater should blow hot air when fully burped.
13. 13

    Final fill and cap installation
    With the engine at operating temperature, top off the radiator to the base of the filler neck. Install the radiator cap securely. Rev the engine to 2000 RPM briefly and verify no coolant leaks appear at either hose connection.

Reassembly

1. Reinstall radiator cap after final fill and burping procedure
2. Wipe down all coolant spills from engine bay and radiator with shop rags
3. Properly dispose of old coolant at an automotive recycling center or hazardous waste facility

Verification

• Start engine and allow to reach full operating temperature while monitoring for leaks at both hose connections
• Check coolant level after engine cools - top off if necessary to base of filler neck
• Squeeze upper radiator hose after engine reaches temperature to verify firm pressure indicating proper thermostat operation
• Monitor coolant level and check for leaks after first drive cycle (25-50 miles)

More procedures for this vehicle