Heater Hoses Replacement Inlet

Tools Required

J 38723 Heater Line Quick Connect Separator

1. Remove the gas mass sensor/mixture control valve (GMS/MCV) and mounting bracket. Refer to Gas Mass Sensor/Mixture Control Valve and Mounting Bracket Replacement in Engine Controls of the C/K Bi-Fuel Supplement.
2. Remove the engine coolant. Refer to Draining and Filling Cooling System in the C/K Truck Service Manual.
3. Disconnect the inlet hose from the generator bracket.
4. Disconnect the inlet hose from the fender clips.
5. Remove the clamps at the tee fitting.
6. Disconnect the tee fitting from the inlet hose.
7. Disconnect the inlet hose from the heater core.
8. Disconnect the inlet hose section from the heater core.
9. Push the inlet hose into the connector.
10. Insert the J 38723 or equivalent into the connector to release the locking tabs.
11. Pull the retainer and the hose from the heater inlet connector.
12. Inspect the O-ring sealing surface on the hose/pipe.

•	If replacing the hose, it must be cut to allow for installation of the tee fitting. Cut the inlet hose 38 cm (15 in) from the heater core end of the hose.

•	If replacing the heater inlet connector, remove the retainer from the hose. Discard the retainer, as the replacement connector is equipped with a retainer.

•	If replacing the hose, remove the retainer from the hose and reinsert the hose into the connector.

•	If reusing the hose and the connector, the retainer can remain in place on the hose.

1. Push the hose into the connector until the retainer tabs lock.
2. Pull back on the hose to check for proper engagement.
3. Connect the inlet hose section to the heater core.
4. Connect the inlet hose clamp to the heater core.
5. Connect the tee fitting to the inlet hose.
6. Install the clamps at the tee fitting.
7. Connect the inlet hose to the fender clips.
8. Install the engine coolant and check the system for leaks. Refer to Draining and Filling Cooling System in the C/K Service Manual.
9. Install the GMS/MCV and mounting bracket. Refer to Gas Mass Sensor/Mixture Control Valve and Mounting Bracket Replacement in Engine Controls of the C/K Bi-Fuel Supplement.

Heater Hoses Replacement Outlet

1. Remove the gas mass sensor/mixture control valve (GMS/MCV) and mounting bracket. Refer to Gas Mass Sensor/Mixture Control Valve and Mounting Bracket Replacement in Engine Controls of the C/K Bi-Fuel Supplement.
2. Remove the engine coolant. Refer to Draining and Filling Cooling System in the C/K Truck Service Manual.
3. Disconnect the outlet hose from the fender clips.
4. Remove the clamps at the tee fitting.
5. Remove the tee fitting from the outlet hose.
6. Remove the outlet hose clamp from the heater core.
7. Remove the outlet hose section from the heater core.
8. Remove the outlet hose mounting screw.
9. Disconnect the outlet hose from the generator bracket.
10. Disconnect the outlet hose clamp from the water pump.
11. Disconnect the outlet hose from the water pump.
12. If replacing the hose, it must be cut to allow for installation of the tee fitting.

Cut the outlet hose 33 cm (13 in) from the heater core end of the hose.

1. Connect the outlet hose to the water pump.
2. Connect the outlet hose clamp to the water pump.
3. Connect the outlet hose to the generator bracket.

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.

4. Install the generator bracket mounting screw.

Tighten
Tighten the screw to 30 N·m (22 lb ft).

5. Connect the outlet hose section to the heater core.
6. Connect the outlet hose clamp to the heater core.
7. Install the tee fitting in the outlet hose.
8. Install the clamps at the tee fitting.
9. Connect the outlet hose to the fender clips.
10. Install the engine coolant and check the system for leaks. Refer to Draining and Filling Cooling System in the C/K Service Manual.
11. Install the GMS/MCV and mounting bracket. Refer to Gas Mass Sensor/Mixture Control Valve and Mounting Bracket Replacement in Engine Controls of the C/K Bi-Fuel Supplement.