Hummer H2. Manual - part 1400

Fig. 57: Using Special Tools For Fan Clutch 
Courtesy of GENERAL MOTORS CORP. 

4. Install the J 46406 to the fan clutch. See Special Tools and Equipment . 

Tighten: Tighten the nut clockwise to 59 N.m (44 lb ft). 

5. Install the fan shroud. Refer to Fan Shroud Replacement . 

 

2004 Hummer H2 

2004 ENGINE Engine Cooling - Hummer H2

  

THERMOSTAT HOUSING REPLACEMENT

Removal Procedure 

IMPORTANT: The thermostat is not serviceable separately. The thermostat housing (water 

pump inlet) and thermostat must be replaced as an assembly.

 

2004 Hummer H2 

2004 ENGINE Engine Cooling - Hummer H2

  

Fig. 58: Air Cleaner Outlet Duct 
Courtesy of GENERAL MOTORS CORP. 

1. Drain the cooling system/engine block. Refer to Draining and Filling Cooling System .  

2. Loosen the air cleaner outlet duct clamps at the throttle body and at the Mass airflow (MAF) sensor.  

3. Remove the air cleaner outlet duct. 

Fig. 59: Water Pump Inlet & Thermostat Housing 
Courtesy of GENERAL MOTORS CORP. 

4. Remove the radiator outlet hose.  

5. Remove the thermostat housing bolts.  

6. Remove the thermostat housing from the water pump.  

Installation Procedure 

 

2004 Hummer H2 

2004 ENGINE Engine Cooling - Hummer H2

  

Fig. 60: Water Pump Inlet & Thermostat Housing 
Courtesy of GENERAL MOTORS CORP. 

1. Install the thermostat housing to the water pump.  

2. Install the thermostat housing bolts. 

Tighten: Tighten the bolts to 15 N.m (11 lb ft). 

3. Install the radiator outlet hose. 

NOTE:

Refer to Fastener Notice in Cautions and Notices.

 

2004 Hummer H2 

2004 ENGINE Engine Cooling - Hummer H2