Coolant Outlet

This procedure covers the removal and replacement of the coolant outlet on the 2024 Rivian EDV 500 dual motor AWD electric delivery van, including draining and refilling the EV battery/motor coolant system.

Warnings

Tools required

Parts

• Coolant outlet assembly × 1 — Use OEM specification
• Coolant outlet gasket/O-ring × 1 — Use OEM specification
• Coolant temperature sensor (if integrated) × 1 — Use OEM specification
• Hose clamps (if damaged) × 2 — Use OEM specification

Fluids

• EV Battery/Motor Coolant — 10 qt

Preparation

1. Park vehicle on level surface and engage parking brake
2. Ensure the vehicle has been off for at least 2 hours to allow cooling system to cool completely
3. Verify 12V battery is fully charged, as the procedure requires accessory power
4. Disconnect 12V negative battery terminal and wait 2 minutes
5. Remove front lower splash shield and underbody panels to access coolant drain points
6. Place coolant drain pan under the vehicle positioned to catch coolant from radiator drain
7. Have replacement coolant ready - verify it is the correct EV-specific coolant type

Procedure

1. 1

   Access high voltage service disconnect
   Open the rear cargo area and locate the high voltage service disconnect panel. Remove the panel cover by releasing the clips. Pull the service disconnect handle to the OFF position and remove the service plug. Store the plug in a secure location away from the vehicle. Wait 5 minutes for high voltage capacitors to discharge.
2. 2

   Drain cooling system
   Locate the coolant reservoir in the front compartment. Slowly remove the reservoir cap to relieve any residual pressure. Position drain pan under the front of the vehicle. Open the radiator drain valve (if equipped) or remove the lower radiator hose at the lowest point to drain the coolant. Allow the system to drain completely, which may take 10-15 minutes.
3. 3

   Remove front motor cover
   Remove the front motor access cover by removing the Torx T30 fasteners securing it to the subframe. There are typically 6-8 fasteners around the perimeter. Carefully lift the cover away, being mindful of any wiring harnesses or clips attached to it.
4. 4

   Disconnect coolant temperature sensor
   Locate the coolant outlet assembly on the front drive unit. Identify the coolant temperature sensor connector (if equipped on the outlet). Press the connector locking tab and carefully pull the connector straight off the sensor. Do not pull on the wires.
5. 5

   Release coolant hose clamps
   Using hose clamp pliers, compress and slide the spring-type hose clamps away from the coolant outlet. There are typically two coolant hoses connected to the outlet - one inlet and one outlet. Mark the hoses with tape to ensure correct reinstallation. Be prepared for residual coolant to drain when hoses are removed.
6. 6

   Remove coolant hoses
   Carefully twist and pull the coolant hoses off the outlet fittings. If hoses are stuck due to age or sealant, use a gentle back-and-forth twisting motion. Do not use excessive force or pry tools that could damage the hose connections or drive unit housing. Allow any remaining coolant to drain into the pan.
7. 7

   Remove coolant outlet fasteners
   Remove the bolts securing the coolant outlet to the drive unit housing. These are typically 10mm head bolts. There are usually 2-4 bolts depending on the outlet design. Keep track of bolt locations as they may be different lengths. Note the position of any brackets or ground straps attached to these bolts.
8. 8

   Remove coolant outlet assembly
   Carefully pull the coolant outlet assembly straight out from the drive unit housing. If the outlet is stuck, gently wiggle it while pulling to break the gasket seal. Do not pry against the drive unit housing or use excessive force. Once removed, inspect the outlet for cracks, corrosion, or damage to the sealing surfaces.
9. 9

   Clean mating surfaces
   Thoroughly clean the drive unit housing mating surface where the coolant outlet seals. Remove all traces of old gasket material, coolant residue, and debris using a plastic scraper and clean shop towels. Do not use metal scrapers that could damage the aluminum housing. Ensure the surface is completely clean and dry before installing the new outlet.
10. 10

    Install new coolant outlet
    Install the new gasket or O-ring onto the replacement coolant outlet, ensuring it is properly seated in the groove. If the coolant temperature sensor is separate, install it into the new outlet first. Apply a thin film of fresh coolant to the gasket to aid installation. Align the outlet with the housing and press it firmly into place by hand, ensuring the gasket seats evenly.
11. 11

    Install outlet fasteners
    Install the coolant outlet bolts and any brackets or ground straps in their original positions. Thread all bolts by hand first to ensure proper alignment. Tighten the bolts in a criss-cross pattern to ensure even gasket compression. Since no torque specification is provided, tighten bolts firmly but do not over-torque the fasteners into the aluminum housing - approximately 15-18 ft-lbs is typical for this application.
12. 12

    Reconnect coolant hoses
    Push the coolant hoses fully onto the outlet fittings until they bottom out. Ensure each hose is installed on the correct fitting as marked during removal. Slide the spring clamps back into position over the hose connections. Verify each clamp is positioned in the groove on the fitting and is properly compressed around the hose.
13. 13

    Reconnect electrical connections
    Reconnect the coolant temperature sensor connector, pressing it on until it clicks and locks into place. Gently tug on the connector to verify it is secure. Reinstall the front motor cover and secure with all Torx T30 fasteners.
14. 14

    Refill cooling system
    Close all drain valves and ensure all connections are secure. Using a funnel, slowly fill the coolant reservoir with fresh EV battery/motor coolant. Fill to the MAX line. If available, use a cooling system vacuum fill tool to evacuate air from the system before filling. This is critical for preventing air pockets in the battery cooling circuit.
15. 15

    Bleed cooling system
    Reconnect the 12V battery. With the high voltage system still disconnected, turn the vehicle to accessory mode. Using Rivian service software, activate the coolant pump bleed function to circulate coolant and purge air from the system. Monitor the coolant reservoir level and add coolant as needed. Run the bleed procedure for the manufacturer-specified time, typically 10-15 minutes. Check for leaks at the coolant outlet during this process.

Reassembly

1. Reinstall all underbody panels and splash shields removed for access
2. Wipe down any coolant spills in the engine compartment
3. Verify the coolant reservoir is filled to the proper level with the system cold
4. Reinstall the high voltage service disconnect plug and verify the handle is in the ON position
5. Close all access panels and secure properly

Verification

• With the high voltage system reconnected, power on the vehicle and verify no cooling system fault codes are present
• Allow the vehicle to reach operating temperature and monitor for leaks at the coolant outlet connections
• Check coolant level after reaching operating temperature and top off if necessary
• Verify the coolant temperature reading is normal and within manufacturer specifications using service software
• Test drive the vehicle and monitor drive unit temperatures to ensure proper cooling system operation
• Recheck coolant level after test drive and after 24 hours of operation
• Verify no coolant puddles under the vehicle after overnight parking

More procedures for this vehicle