Hummer H1 (2006+). Manual - part 183

4-12

Cooling System

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SURGE TANK-TO-RADIATOR BLEEDER HOSE REPLACEMENT

Removal

1.

Depressurize the cooling system.

2.

Loosen the two clamps and remove the radiator vent hose from the radiator and the surge tank (Figure  4-10).

3.

Reclaim the coolant. 

Installation

1.

Secure the radiator vent hose to the surge tank and the radiator with the two clamps (Figure  4-10).

2.

Replace the coolant.

3.

Tighten the coolant filler cap.

THERMOSTAT BYPASS PIPE REPLACEMENT

Removal

1.

Disconnect the battery.

2.

Drain the cooling system.

3.

Release the serpentine belt.

4.

Remove the larger center idler pulley.

5.

Disconnect the rubber hose from the bypass pipe.

6.

Disconnect the bypass pipe from the water cross over and the water pump.

7.

Remove the water bypass pipe (Figure  4-11).

Installation

NOTE: If installing the same bypass pipe that was removed. Inspect the o rings for damage before installation.

1.

Secure the bypass hose to the water pump and the water crossover (Figure  4-11).

2.

Connect the rubber hose from the turbo to the bypass pipe.

3.

Install the larger center idler pulley.

4.

Install the serpentine belt.

5.

Fill the cooling system. See cooling system service for proper filling and bleeding procedure.

6.

Reconnect the battery.

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 Cooling System  4-13

5745804

Figure 4-11:   Thermostat Bypass Hose Replacement

WATER BYPASS

TUBE

WATER

BYPASS

O-RINGS

WATER CROSS 

OVER PIPE

WATER OUTLET

PIPE

THERMAL ENGINE

 WATER VALVE

WATER OUTLET

PIPE O-RING

4-14

Cooling System

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WATER OUTLET PIPE THERMOSTAT TO UPPER RADIATOR HOSE REPLACEMENT

Removal

1.

Disconnect the battery.

2.

Depressurize the cooling system.

3.

Drain the cooling system as necessary.

4.

Disconnect the transmission control harness connector behind the AC compressor and remove the harness mount bracket.

5.

Remove the charge air pipe above the engine harness connectors.

6.

Disconnect the engine harness connectors and remove the harness mount bracket.

7.

Remove the serpentine belt.

8.

Remove the P clamp securing the AC lines and the two AC compressor connectors.

NOTE: It is not necessary to evacuate the AC system as the system can be moved out of the way.

9.

Remove the AC compressor, AC lines assembly and set aside.

10. Remove the thermal engine water valve (Figure  4-11).

11. Disconnect the upper radiator hose from the water outlet pipe.

12. Remove the water outlet pipe (Figure  4-11).

Installation

NOTE: If installing the same water outlet pipe that was removed. Inspect the o ring for damage before installation. 

1.

Install the water outlet pipe into the water cross over pipe and secure.

2.

Install the water outlet pipe into the upper radiator hose and secure.

3.

Install the thermal engine water valve into the water outlet pipe.

4.

Install the AC compressor and the two AC compressor connectors.

5.

Secure the AC lines with the P clamp.

6.

Install the serpentine belt.

7.

Install the engine harness mount bracket and the engine harness connectors.

8.

Install the charge air pipe.

9.

Install the transmission control harness mount bracket and the transmission control harness connector.

10. Fill the cooling system. See cooling system service for proper filling and bleeding procedure.

11. Connect the battery.

UPPER RADIATOR HOSE REPLACEMENT

Removal

1.

Depressurize the cooling system.

2.

Drain the cooling system as necessary.

3.

Loosen the clamps and remove the hose from the thermostat housing and the radiator (Figure  4-12).

Installation

1.

Secure the upper radiator hose to the thermostat housing and the radiator with the clamps (Figure  4-12).

2.

Fill the cooling system. See cooling system service for proper filling and bleeding procedure.

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 Cooling System  4-15

5745804

Figure 4-12:   Upper Radiator Hose Location

LOWER RADIATOR HOSE REPLACEMENT

Removal

1.

Drain the cooling system.

2.

Loosen the clamps and remove the lower radiator hose from the radiator and the lower tube assembly (Figure  4-13).

Installation

1.

Secure the lower radiator hose to the lower tube assembly and the radiator with the clamps (Figure  4-13).

2.

Fill the cooling system. See cooling system service for proper filling and bleeding procedure.

RADIATOR LOWER TUBE ASSEMBLY REPLACEMENT

Removal

1.

Drain the cooling system.

2.

Remove the drain valve from the lower tube assembly (Figure  4-13).

3.

Disconnect the radiator lower tube assembly from the frame bracket.

4.

Loosen the clamp and disconnect the water pump inlet hose from the lower tube assembly.

5.

Loosen the clamp and disconnect the surge tank-to-lower radiator hose from the lower tube assembly.

6.

Loosen the clamp and disconnect the lower radiator hose from the lower tube assembly.

7.

Remove the lower tube assembly.

Installation

1.

Secure the lower tube assembly to the frame bracket with the bolts, washers, and locknuts. Tighten the locknuts to 6 lb-ft (8
N•m) (Figure  4-13).

2.

Connect the lower radiator hose to the lower tube assembly and tighten the clamp.

3.

Connect the surge tank-to-lower radiator hose to the lower tube assembly and tighten the clamp.

4.

Connect the water pump inlet hose to the lower tube assembly and tighten the clamp.

5.

Apply sealant tape to the threads of the drain valve and screw the drain valve into the lower tube assembly.

6.

Fill the cooling system. See cooling system service for proper filling and bleeding procedure.

RADIATOR

CLAMP

THERMOSTAT

HOUSING

UPPER RADIATOR

HOSE

CLAMP

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