Coolant Reservoir

Remove and replace the coolant reservoir (expansion tank) on a 1992 Dodge Viper RT/10, including draining coolant, disconnecting hoses, and refilling the cooling system.

Warnings

Tools required

Parts

• Coolant reservoir × 1 — Use OEM specification
• Reservoir cap (if damaged) × 1 — Use OEM specification

Fluids

• Ethylene glycol 50/50 — 3 qt

Preparation

1. Ensure engine is completely cold to the touch (minimum 2 hours after last operation)
2. Park vehicle on level surface and engage parking brake
3. Place drain pan under radiator drain petcock location at driver-side lower radiator tank
4. Remove coolant reservoir cap slowly to release any residual pressure

Procedure

1. 1

   Drain coolant from system
   Open the radiator drain petcock at the bottom of the driver-side radiator tank by turning counterclockwise. Allow approximately 3-4 quarts to drain into the pan. This reduces coolant loss and mess during reservoir removal. Close petcock hand-tight when draining slows to a trickle.
   Torque spec

   Drain Petcock7 Nm (5 lb-ft)
2. 2

   Locate coolant reservoir
   The coolant reservoir (expansion/overflow tank) is a translucent plastic tank with MIN/MAX level markings. Verify its exact mounting location against the 1992 Viper factory service manual before proceeding, as engine-bay layout differs from conventional vehicles. Identify the upper hose connection at the reservoir neck and the lower overflow hose at the bottom.
3. 3

   Disconnect upper coolant hose
   The upper hose connects the reservoir to the radiator filler neck. Loosen the spring-type or worm-gear hose clamp at the reservoir using hose clamp pliers or a flat-blade screwdriver. Slide the clamp back along the hose away from the reservoir neck. Twist the hose gently to break the seal, then pull it off the reservoir neck. Expect residual coolant spillage; have shop rags ready.
4. 4

   Disconnect lower overflow hose
   The lower overflow hose runs from the bottom of the reservoir to the radiator overflow port. Loosen the hose clamp at the reservoir connection using the same method as Step 3. Remove the hose from the reservoir nipple. Allow any trapped coolant to drain into the pan.
5. 5

   Remove reservoir mounting bolts
   The reservoir is secured to the mounting bracket with mounting bolts. Verify the exact bolt count and head size against the 1992 Viper factory service manual before removal. Remove both bolts completely and set aside. Lift the reservoir straight up and out of the engine bay. Inspect the mounting bracket for cracks or damage.
   Torque spec

   Reservoir Mounting Bolts8 Nm (6 lb-ft)
6. 6

   Inspect and prepare new reservoir
   Compare the new reservoir to the old unit to confirm correct fitment, including hose nipple locations and mounting hole positions. Transfer the reservoir cap to the new unit if the cap is in good condition (no cracks, seal intact, pressure release functioning). If the cap shows wear, replace it with a new OEM-specification cap rated for the Viper cooling system pressure.
7. 7

   Install new reservoir
   Position the new reservoir into the mounting bracket on the inner fender, aligning the mounting holes. Install both 8mm mounting bolts and torque to specification in an alternating pattern to ensure even seating.
   Torque spec

   Reservoir Mounting Bolts8 Nm (6 lb-ft)
8. 8

   Reconnect overflow hose
   Push the lower overflow hose firmly onto the reservoir bottom nipple until fully seated. Position the hose clamp over the hose-to-nipple connection and tighten to specification. Ensure the clamp is positioned over the hose bead area for proper sealing.
   Torque spec

   Hose Clamps4 Nm (3 lb-ft)
9. 9

   Reconnect upper coolant hose
   Push the upper radiator hose onto the reservoir neck until fully seated against the neck flange. Position the hose clamp over the connection point and tighten to specification. Verify the hose is not kinked and has adequate clearance from moving components.
   Torque spec

   Hose Clamps4 Nm (3 lb-ft)
10. 10

    Refill cooling system
    Using a funnel, refill the cooling system with ethylene glycol 50/50 mixture at the proper fill point per the factory service manual, then top off the reservoir to the MAX line. Do not overfill. Start the engine and allow it to warm to operating temperature (thermostat open, approximately 5-7 minutes at idle). Monitor coolant level in the reservoir as air pockets purge from the system. Add coolant as needed to maintain level between MIN and MAX marks. Follow the factory service manual bleeding procedure for the Viper V10 cooling system, as trapped air in a large-capacity system can cause overheating if not properly purged.
11. 11

    Pressure test system
    With the engine at operating temperature, carefully reinstall the reservoir cap. Increase engine speed to 2000 RPM for 30 seconds, then return to idle. Inspect all hose connections at the reservoir for leaks. Check the reservoir mounting area and hose routing for any coolant seepage. Shut off engine and allow to cool for 10 minutes, then recheck coolant level and top off if necessary.

Reassembly

1. All reassembly steps are integrated into the removal procedure above
2. Ensure reservoir cap is securely tightened after final coolant level check
3. Dispose of old coolant reservoir and drained coolant according to local environmental regulations

Verification

• Coolant level is between MIN and MAX marks on reservoir when engine is cold
• No coolant leaks visible at either hose connection after two heat cycles (cold to operating temperature and back)
• Reservoir is firmly mounted with no movement when pushed by hand
• Engine maintains normal operating temperature (190-210°F) with no overheating or temperature fluctuations
• After 24 hours and normal driving, recheck coolant level and inspect for any seepage at connections

Related trouble codes on this vehicle

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