Hypertech Thermostat Replacement

hypertech.jpg (9771 bytes)

When adding coolant, it is important that you use GM Goodwrench DEX-COOL™ coolant. If coolant other than DEX-COOL™ is added to the system, the engine coolant will require change sooner: at 50 000 km (30,000 miles) or 24 months.

    Removal Procedure

    1. Disconnect the negative battery cable.
    2. Drain and recover the coolant.
    3. Remove the air cleaner assembly.
    4. Remove the surge tank line from the coolant outlet.
    5. Remove the coolant outlet to the inlet manifold attaching bolts.
    6. Remove the coolant outlet.
    7. Remove the thermostat.
    8. Clean the inlet manifold mating surfaces.
    9. Clean the coolant outlet mating surfaces.

    Installation Procedure
    1. Install the thermostat in the inlet manifold.
    2. Install the coolant outlet to the inlet manifold.  
    3. Install the attaching bolts. Tighten
    4. Install the air cleaner assembly.
    5. Install the surge tank line to the coolant outlet.
    6. Fill the engine with coolant.
    7. Connect the negative battery cable. Tighten
    8. Inspect the system for leaks.



**information gathered from General Motors Vehicle Service Manual 1999