The 1996 GMC Jimmy came with a 4.3-liter six-cylinder and a four-speed automatic transmission with or without four-wheel drive. The water pump on your engine pushes coolant through the engines coolant passages, heater core and radiator to keep the engine cool and provide heat to the passenger cabin. Whenever the water pump fails you have to remove the fan and replace the coolant. Your engine uses DEXCOOL coolant and has a total capacity of 13 quarts.
Instructions
- 1
Lift the hood and allow the engine to cool. Rotate the radiator cap a quarter turn to release pressure and then remove it. Jack the front of the vehicle up and support it with jack stands under the frame rails. Place a drain pan under the passenger side corner of the radiator. Rotate the drain cock counterclockwise and allow all the coolant to drain.
2Place the drain pan under either side of the engine and remove the block drain plug. Repeat for the other side of the engine; the plugs will be just below the cylinder head on the block. Clean the plugs with a wire brush and replace. Tighten the plugs with a socket and ratchet. Store the used coolant in a safe place away from children and animals.
3Remove the bolts securing the upper fan shroud to the lower fan shroud. Pry the center pin of the push-pin connectors securing the shroud to the core support and remove them. Remove the upper fan shroud.
Remove the fan and fan clutch with the fan clutch tool. The fan nut rotates counterclockwise for removal; use the holding tool on the pulley bolts when loosening.
Draw out a sketch of the serpentine belt routing and store it in a safe place. Rotate the belt tensioner counterclockwise with a breaker bar and socket on the pulley bolt and remove the belt from the engine. Remove the four bolts securing the water pump pulley to the pump hub and remove the water pump pulley.
5Loosen the clamps for the water pump hoses and remove the hoses from the water pump. Inspect the hoses and clamps and replace them as necessary. Remove the four bolts securing the water pump to the engine. Remove the water pump from the engine. Clean the mating surfaces on the engine with a wire brush so you know the new pump and gasket will seal correctly. Position new gaskets and install the water pump. Tighten the mounting bolts to 30 foot-pounds.
6Connect the hoses to the water pump and secure them with the hose clamps. Place the pulley on the new pump hub and install the mounting bolts. Tighten the bolts to 18 foot-pounds. Route the belt around the pulley system according to the sketch you made earlier. Rotate the tensioner counterclockwise and slide the belt into position. Release the tensioner.
7Thread the fan and fan clutch onto the water pump hub. Tighten the center bolt to 18 foot-pounds with a torque wrench and crowfoot attachment. Set the upper fan shroud into place and tighten the mounting bolts. Install the push pin retainers to secure the shroud to the core support.
8Remove the jack stands from under the vehicle and lower the vehicle to the ground. Slowly add fresh DEXCOOL coolant to the radiator until the coolant holds steady at the fill neck. Set the heater controls to max heat. Start the engine and allow it to reach operating temperature; the upper radiator will get hot when this happens. Continue to add Dexcool to the radiator until the level holds steady at the fill neck. Fill the over flow tank to full hot. Hold engine speed at 2500 RPM for 2 minutes and add coolant as necessary. Install the radiator cap, shut the hood and turn off the vehicle.
9Any remaining air in the cooling system will work its way to the overflow as you drive the vehicle. Check the coolant level after 50 miles and top off as necessary. Take the used coolant to a local repair shop for disposal.
