Cooling Fan Motor

Replace the cooling fan motor on a 1992 Dodge Viper 8.0L V10, including removal of the fan shroud assembly and associated electrical connections.

Warnings

Tools required

Parts

• Cooling fan motor × 1 — Use OEM specification
• Radiator cap gasket (if damaged) × 1 — Use OEM specification

Fluids

• coolant — 3 qt

Preparation

1. Ensure engine is completely cool to the touch (minimum 2 hours after last operation).
2. Position vehicle on level ground and engage parking brake.
3. Open hood and secure in upright position.
4. Disconnect negative battery cable to prevent accidental fan engagement.
5. Place drain pan under radiator drain petcock location on driver's side lower radiator tank.

Procedure

1. 1

   Drain cooling system
   Remove radiator cap by pressing down and turning counterclockwise. Locate the drain petcock on the lower driver's side of the radiator. Open the petcock by turning counterclockwise and allow coolant to drain into the pan. The system holds approximately 24 quarts total; you will drain approximately 2-3 quarts for fan motor access.
2. 2

   Remove upper radiator hose
   Locate the upper radiator hose connection at the radiator inlet at the top of the radiator (verify inlet side for this vehicle). Use pliers or a flat-blade screwdriver to loosen the hose clamp by either squeezing the spring clamp tabs or turning the screw clamp counterclockwise. Slide the clamp back along the hose away from the radiator neck. Twist the hose gently to break the seal, then pull it off the radiator inlet. Be prepared for residual coolant spillage.
3. 3

   Disconnect cooling fan electrical connector
   Locate the cooling fan motor electrical connector mounted on the fan shroud assembly. Press the locking tab on the connector and pull the two halves apart. Route the wiring harness clear of the shroud assembly for removal access.
4. 4

   Remove fan shroud mounting bolts
   Locate the fan shroud mounting bolts securing the shroud to the radiator support brackets. There are 4 bolts total: two along the top edge of the shroud and two at the lower corners. Remove all 4 bolts using an appropriate metric socket. Support the shroud assembly as you remove the final bolt.
5. 5

   Remove fan shroud assembly
   Carefully lift the fan shroud assembly straight up and out of the engine compartment. The shroud may need to be tilted slightly to clear the fan blades and surrounding components during removal. Set the shroud on a clean work surface with the fan motor facing up.
6. 6

   Remove fan blade from motor
   With the shroud assembly on the bench, locate the fan blade retaining nut or clip on the motor shaft. If equipped with a nut, hold the motor shaft from behind to prevent rotation and remove the retaining nut (verify thread direction before loosening). If equipped with a spring clip, use pliers to remove the clip. Slide the fan blade off the motor shaft. Note the orientation of any spacers or washers for reinstallation.
7. 7

   Remove cooling fan motor from shroud
   Locate the fan motor mounting bolts securing the motor housing to the shroud (typically 3 bolts arranged in a triangular pattern). Remove all motor mounting bolts and carefully separate the motor from the shroud. Inspect the shroud mounting surface for cracks or damage.
8. 8

   Install new cooling fan motor
   Position the new cooling fan motor on the shroud mounting surface, aligning the mounting holes. Install all motor mounting bolts finger-tight, then torque to specification in a cross-pattern to ensure even seating. Verify the motor shaft rotates freely without binding.
   Torque spec

   Fan Motor Bolts8 Nm (6 lb-ft)
9. 9

   Install fan blade on new motor
   Slide the fan blade onto the motor shaft, ensuring any spacers or washers are installed in the correct order as noted during removal. Install the retaining nut or clip to secure the blade. If using a nut, hold the motor shaft to prevent rotation and torque the nut to secure the blade (hand-tight plus 1/8 turn for clip-type; snug for threaded nut). Verify the blade spins freely without contacting the shroud.
10. 10

    Install fan shroud assembly
    Carefully lower the fan shroud assembly into position on the radiator, ensuring it seats properly on the mounting brackets. Tilt the shroud as needed to clear the surrounding components during installation. Align all mounting holes with the radiator support brackets.
11. 11

    Install shroud mounting bolts
    Install all 4 fan shroud mounting bolts (2 top, 2 bottom) and tighten securely. Do not overtighten, as the shroud is plastic and can crack. Torque to specification if applicable.
12. 12

    Reconnect electrical connector and upper hose
    Connect the cooling fan motor electrical connector, ensuring the locking tab clicks into place. Reinstall the upper radiator hose onto the radiator inlet, pushing it fully onto the neck. Reposition the hose clamp over the connection point and tighten to specification. Ensure the clamp is positioned over the bead on the radiator neck.
    Torque spec

    Hose Clamps4 Nm (3 lb-ft)
13. 13

    Close drain petcock and refill coolant
    Close the radiator drain petcock by turning it clockwise hand-tight. Do not overtighten. Refill the cooling system through the radiator neck with a 50/50 mixture of ethylene glycol coolant and distilled water. Fill until coolant is visible at the radiator neck. Install the radiator cap. Locate and fill the coolant recovery reservoir to the FULL COLD mark.
    Torque spec

    Drain Petcock7 Nm (5 lb-ft)
14. 14

    Bleed cooling system and test fan operation
    Reconnect the negative battery cable. Start the engine and allow it to reach operating temperature with the radiator cap OFF (watch for coolant expansion). Monitor coolant level and add as needed to maintain level at the neck. Once the thermostat opens (indicated by hot upper radiator hose), the cooling fan should cycle on at its specified activation temperature (verify against factory specification). Verify fan operation by observing fan rotation when coolant temperature reaches threshold. Shut off engine, allow to cool slightly, then install radiator cap. Check for leaks around all connections.

Reassembly

1. Reinstall components in reverse order of removal.
2. Ensure all electrical connections are fully seated with locking tabs engaged.
3. Verify hose clamps are positioned over the beaded sections of radiator and hose connections.
4. Double-check all mounting bolts are tightened to specification.

Verification

• Start engine and verify cooling fan does not engage immediately when cold.
• Allow engine to reach operating temperature and verify fan cycles on at approximately 210-220°F.
• Verify fan cycles off when temperature drops below threshold.
• Check for coolant leaks around radiator hose connection and drain petcock.
• Verify coolant level is at proper mark on recovery reservoir after cool-down.
• Listen for unusual fan motor noise or vibration during operation.

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