Water Pump

Replace the water pump on a 2005 Dodge Viper 8.3L V10, including coolant drain, accessory drive belt removal, and system refill with proper bleeding.

Warnings

Tools required

Parts

• Water pump assembly × 1 — Mopar 4864655 or equivalent
• Water pump gasket × 1 — Typically included with pump assembly
• Accessory drive belt × 1 — Use OEM specification for length and profile
• Coolant drain plug O-ring × 1 — Mopar 68048815AA or equivalent

Fluids

• Zerex G-05 HOAT 50/50 coolant — 19 qt

Preparation

1. Park vehicle on level ground and allow engine to cool completely (minimum 3 hours)
2. Disconnect negative battery cable to prevent accidental fan activation
3. Raise front of vehicle and support securely on jack stands
4. Remove engine belly pan if equipped to access lower coolant drain
5. Place large drain pan beneath radiator and engine block drain points
6. Have replacement coolant, water pump, and gasket ready before beginning

Procedure

1. 1

   Drain cooling system
   Open radiator petcock at bottom of radiator driver's side to begin draining coolant into pan. If equipped, locate and remove the engine block coolant drain plug(s) as fitted; verify the number and location against factory service documentation before removal. Capture all coolant for proper disposal. Remove radiator cap to allow complete drainage. Expect approximately 18-19 quarts total system capacity.
2. 2

   Remove accessory drive belt
   Locate the automatic belt tensioner on the front of the engine. Using a 15mm wrench or breaker bar, rotate the tensioner clockwise to release tension on the serpentine belt. Slip the belt off the water pump pulley first, then release tensioner slowly and remove belt from remaining pulleys. Note belt routing path or take photo for reinstallation reference.
3. 3

   Remove cooling fan shroud
   Remove the upper radiator hose from the thermostat housing to provide clearance. Remove the cooling fan shroud mounting bolts (typically 4 bolts securing shroud to radiator support). Carefully lift the fan shroud assembly up and out of the engine bay. Remove the fan/shroud assembly as equipped; note that this platform may use electric cooling fans rather than a belt-driven mechanical fan, so verify configuration before removal.
4. 4

   Disconnect water pump hoses
   Disconnect the lower radiator hose from the water pump inlet. Use hose clamp pliers or screwdriver to release clamps and slide away from connection points. Disconnect any bypass hoses or heater hoses connected to the water pump housing. Mark hose positions if necessary for correct reassembly. Allow residual coolant to drain into pan.
5. 5

   Remove water pump pulley
   Remove the water pump pulley mounting bolts. These are typically 4 bolts securing the pulley to the water pump hub. A strap wrench or pulley holder may be necessary to prevent the pump from rotating while loosening bolts. Remove pulley and set aside.
6. 6

   Remove water pump mounting bolts
   Remove all water pump mounting bolts securing the pump to the engine block. The Viper V10 water pump typically uses 8 bolts around the perimeter of the pump housing. Note bolt lengths and positions as they may vary. Remove bolts in a criss-cross pattern to prevent housing warping.
7. 7

   Remove water pump assembly
   Carefully pull the water pump assembly straight out from the engine block. The pump may be stuck due to gasket seal. Use a plastic pry tool or tap gently with a rubber mallet if necessary, being careful not to damage the mounting surface on the block. Remove and discard old gasket material.
8. 8

   Clean mounting surfaces
   Thoroughly clean the water pump mounting surface on the engine block using a plastic gasket scraper. Remove all traces of old gasket material, corrosion, and debris. Use a wire brush for stubborn areas, being careful not to gouge the aluminum surface. Wipe clean with shop towels. Inspect mounting surface for damage, warping, or deep scratches that could prevent proper seal.
9. 9

   Install new water pump
   Position new gasket on the engine block mounting surface, aligning all bolt holes. Some gaskets are adhesive-backed; others may require a light application of gasket sealant per manufacturer instructions. Carefully position the new water pump assembly onto the block, ensuring gasket remains properly aligned. Start all 8 mounting bolts by hand to prevent cross-threading.
   Torque spec

   Water Pump Bolts25 Nm (18 lb-ft)
10. 10

    Torque water pump bolts
    Torque water pump mounting bolts to 25.0 Nm (18.0 lb-ft) in a criss-cross pattern. Begin with center bolts and work outward to ensure even gasket compression and prevent housing distortion. Verify all bolts are seated properly and torque is even.
    Torque spec

    Water Pump Bolts25 Nm (18 lb-ft)
11. 11

    Reinstall water pump pulley
    Position water pump pulley onto the pump hub and install mounting bolts. Tighten pulley bolts in a star pattern. Use pulley holder or strap wrench to prevent rotation while torquing. Torque pulley bolts to manufacturer specification (typically 25-30 Nm if not provided in database).
12. 12

    Reconnect cooling system hoses
    Reconnect lower radiator hose to water pump inlet. Reconnect all bypass and heater hoses removed earlier. Install new hose clamps or reuse existing clamps if in good condition. Position clamps properly over hose barbs and tighten securely. Ensure all connections are fully seated.
    Torque spec

    Hose Clamps3 Nm (2 lb-ft)
13. 13

    Reinstall fan shroud and upper hose
    Carefully lower the cooling fan shroud assembly back into position, ensuring fan blades clear the shroud properly. Install shroud mounting bolts and tighten securely. Reconnect upper radiator hose to thermostat housing and secure with clamp.
    Torque spec

    Hose Clamps3 Nm (2 lb-ft)
14. 14

    Install accessory drive belt
    Route new accessory drive belt around all pulleys following the routing diagram (typically found on radiator support or hood underside). Rotate belt tensioner clockwise with wrench, slip belt onto final pulley (typically tensioner pulley last), then slowly release tensioner to apply proper tension. Verify belt is properly seated in all pulley grooves with no twists.
15. 15

    Close drains and refill cooling system
    Install new O-ring on the engine block drain plug(s) and reinstall on the cylinder bank(s) as equipped. Tighten securely but do not overtorque; confirm exact torque against factory service documentation. Close radiator petcock. Fill cooling system slowly with Zerex G-05 HOAT 50/50 coolant through radiator filler neck. Fill until coolant reaches bottom of filler neck. Start engine with heater on maximum heat and allow to idle. Add coolant as level drops during bleeding process.
16. 16

    Bleed cooling system
    With engine idling and heater on maximum, watch for coolant circulation in radiator filler neck. Gently squeeze upper radiator hose to help purge air pockets. The Viper V10 may have dedicated air bleed valves on coolant crossover tubes near the thermostat housings - open these briefly to release trapped air. Continue adding coolant as air is purged. Run engine until thermostat opens (coolant temperature reaches approximately 195°F and upper radiator hose becomes hot). Maintain coolant level at filler neck.
17. 17

    Complete fill and pressure test
    Once thermostat has opened and coolant is circulating fully, top off coolant level to bottom of radiator filler neck. Install radiator cap. Allow engine to reach full operating temperature and verify no leaks around water pump, hoses, or drain plugs. Check heater output is hot. Shut off engine and allow to cool. Recheck coolant level when cold and top off as needed. Verify coolant overflow reservoir is at proper COLD mark.

Reassembly

1. Reinstall engine belly pan if removed
2. Lower vehicle from jack stands
3. Reconnect negative battery cable
4. Double-check all hose clamps and connections for security
5. Dispose of old coolant properly at a recycling center or auto parts store
6. Monitor coolant level and temperature gauge for the first several drive cycles to ensure proper bleeding

Verification

• Start engine and verify no coolant leaks around water pump, hoses, or drain plugs
• Confirm coolant circulation by observing flow through radiator filler neck when thermostat opens
• Verify engine reaches normal operating temperature (approximately 195°F) without overheating
• Confirm heater produces hot air at idle and under load
• Check coolant level when cold - should be at bottom of radiator filler neck
• Inspect accessory drive belt for proper tension and alignment on all pulleys
• Listen for abnormal noises from water pump bearing during operation
• After first test drive, recheck coolant level and inspect for any new leaks

More procedures for this vehicle