GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2001 🢒 Express 🢒 Engine 🢒 Engine Cooling 🢒 Engine Coolant Crossover Pipe Replacement

Engine Coolant Crossover Pipe Replacement 8.1L

Removal Procedure

    Object Number: 470789 Size: SH
  1. Remove the drive belt tensioner bolts. Refer to Drive Belt Tensioner Replacement .
  2. Remove the drive belt tensioner. Refer to Drive Belt Tensioner Replacement .

    3. Object Number: 677790 Size: SH
  3. Drain the cooling system. Refer to Cooling System Draining and Filling .
  4. Remove the bypass hose.

    5. Object Number: 470698 Size: SH
  5. Remove the coolant crossover bolts.
  6. Remove the coolant crossover.
  7. Remove the coolant crossover gaskets.

    8. Object Number: 635643 Size: SH
  8. Remove the water outlet bolts (2).
  9. Remove the water outlet (1).
  10. Remove the thermostat (3) from the coolant crossover.

Installation Procedure

    Object Number: 635643 Size: SH
  1. Install the thermostat with the seal into the coolant crossover.
  2. Install the water outlet bolts.

    3. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  3. Install the water outlet bolts.

    4. Tighten
    Tighten the water outlet bolts to 30 N·m (22 lb ft).

  4. Place the coolant crossover gaskets and the coolant crossover in position.
  5. Install the coolant crossover bolts.

    6. Tighten
    Tighten the coolant crossover bolts to 50 N·m (37 lb ft).


    Object Number: 677790 Size: SH
  6. Install the thermostat bypass hose clamps onto the thermostat bypass hose.
  7. Install the thermostat bypass hose.

    8. Important: Properly position the bypass hose clamps to avoid water pump pulley interference.

  8. Position the thermostat bypass hose clamps.

    9. Object Number: 470789 Size: SH
  9. Install the drive belt tensioner.
  10. Install the drive belt tensioner bolts.

    11. Tighten
    Tighten the drive bolt tensioner bolts to 50 N·m (37 lb ft).

  11. Refill the cooling system. Refer to Cooling System Draining and Filling .