GM 12657499 Engine Coolant Pump Kit

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To remove the water pump, start by disconnecting the cable from the negative battery terminal and draining the cooling system. Remove the drivebelt, right-side engine strut mount, and mount bracket. Hold the water pump pulley with a strap wrench or pin spanner and remove the pulley mounting bolts and pulley. Then, remove the water pump mounting bolts and carefully remove the pump from the engine. Clean the mating surface of the engine and the water pump if it will be reinstalled. To install the new water pump, compare it with the old one to ensure they are identical. Place the gasket and water pump into position and install the new mounting bolts. Tighten the water pump mounting bolts in a criss-cross pattern to the specified torque. Finally, tighten the water pump pulley bolts, refill the cooling system with the proper antifreeze concentration, and start the engine to check for leaks while it reaches normal operating temperature.

Disconnect the cable from the negative battery terminal. Raise the vehicle and support it securely on jackstands. Remove the under-vehicle splash shield. Drain the cooling system. If the coolant is relatively new and in good condition, save it and reuse it. Once the coolant has drained, lower the vehicle. Remove the drivebelt. Remove the air filter housing and air intake duct/resonator. For V6 engines, use a pin spanner or strap wrench to hold the water pump pulley from turning, and remove the pulley mounting bolts and pulley. Remove the bolts attaching the water pump to the timing chain cover and remove the pump from the engine. If the water pump is stuck, gently tap it with a soft-faced hammer to break the seal. Clean the bolt threads and the threaded holes in the engine and remove all corrosion and sealant. Remove all traces of old gasket material from the sealing surfaces. For V8 engines, remove the engine cover. On non-supercharged models, remove the drivebelt tensioner and the idler pulley mounting bolt and pulley. On supercharged models, remove the supercharger drivebelt and tensioner, then remove the tensioner bracket bolts and bracket. Disconnect and remove the hoses to the water pump. Unbolt and remove the water pump from the front of the engine. It may be necessary to tap the pump with a soft-face hammer to break the gasket seal. To install, remove the gaskets from the engine, then compare the new pump and replacement gaskets to the old ones to make sure that they're identical. Apply a thin film of RTV sealant to hold the new gasket in place during installation. O-rings should be coated with clean coolant. Make sure the gasket is correctly positioned on the water pump and the mating surfaces are clean and free of old gasket material. Carefully mate the pump to the water pump housing. On V6 models, install the bolts and, following the recommended sequence, tighten the bolts to the torque. On V8 models, install the water pump bolts and tighten them, a little at a time, to the torque. The remainder of installation is the reverse of removal. Refill the cooling system. Operate the engine to check for leaks.

To remove the condenser on 2007 and earlier models, unclip it. In 2010 and later models, the condenser must be completely removed. Inspect the radiator for leaks and damage, and if necessary, use special techniques for repair. Bugs and dirt can be removed from the radiator by spraying it with a garden hose nozzle from the back side, and it should be flushed out with a garden hose before installation. For installation, guide the condenser/radiator/fan assembly into position, ensuring that the rubber mounts on the bottom are properly seated into the support. Tighten the radiator and air conditioning condenser bracket bolts securely. Fill the cooling system with the proper mixture of antifreeze and water, start the engine, and check for leaks. Allow the engine to reach normal operating temperature, then recheck the coolant level and add more if required. Finally, check the transaxle fluid and add more as needed.

An overheating engine could result due to water pump failure. In such a case, the coolant will leak from the engine front cover or an externally exposed hole next to the shaft seal in case of failure of the shaft seal. Weep or vent holes are provided in water pumps. Using a flashlight, one can check whether there is any leakage on the water pump weep hole(s). If the shaft seal breaks, then there will be coolant leakages through that hole. Use your flashlight and find hole(s) on the water pump that you should check for leaks at. The hole (s) usually exist at either top or bottom of the pump body around its shaft seal area. When running, a whining noise could be heard from a water pump if its bearings have failed on its shaft. Shaft wear can be felt with the engine off if you rock the water pump's pulley up-and-down. Water pump bearing failure should not be mistaken with drivebelt slippage, which makes squealing sound when it occurs. Turning on your heater is a quick way to check your water pump performance. It might not be able to circulate hot water efficiently all the way to core if it is failing or has already failed since hot steam would also not make it there directly.

To begin, take off the drive belt and drain the coolant, ensuring any spilled coolant is cleaned. On four-cylinder engines, search for an additional drain plug on the bottom of the water pump. For four-cylinder engines, detach the electrical connector for the ECT sensor and remove it as well as any straps connected to thermostat housing. Take off the outlet hose from the expansion tank and also take out the radiator hose from outlet cover. Remove heat shield for exhaust manifold. Disconnect heater hoses from thermostat housing; pull out housing mounting bolts; then take away water pipe from thermostat housing and replace old O-ring seals with new ones. Loosen lug nuts of right front wheel, raise vehicle, and remove wheel and fender splash shield. Install a special tool to hold the sprocket of water pump; or put a homemade tool to hold it in place, using this tool remove all water pump-to-sprocket bolts: then remove water pump from engine. Clean threads of bolts, threaded holes and sealing surfaces-get rid of all old gasket material and ring sealing in order to clean up space inside water pumps.Install new sealing ring (place it on) and fit in place sprocket together with your water pump. Finally fasten water pump mounting bolts so that you could move on to next step for tightening them sprocket bolts; after this stage you can lubricate seal light by silicone gel before installing rear cover for timing belt, thermostat housing/water pipe.Complete reverse process including reinstallation of drive belt tightening pulley bolts down; refilling cooling system with proper concentration of antifreeze.Reinstalling these components involves reverse procedure including: loosening water pump pulley bolts after removing air duct on V6 engines.Withdraw pulley and also unfasten some mounting bolts that usually secure your water pumps onto engine block.Clean those threads which attach mountings into your engine's threaded holes-first check if replacement pump is suitable, you may then clean surfaces which touch it with lacquer thinner or acetone, and use RTV sealant on new gasket. Assemble gasket with water pump and install it by attaching bolts for mounting water pumps and pulleys respectively.The final step is to fill coolant by following the procedure of filling cooling system until engine gets to normal operating temperature while carefully checking for any possible leakages as well.

A failure in the water pump can lead to serious engine damage as it causes overheating. These models have a water pump that is driven by the drivebelt. Water pumps are typically equipped with weep or vent holes, which can leak coolant if there is a failure in the pump seal. To check for leaks, a flashlight and small mirror can be used to locate the hole on the water pump. If the water pump shaft bearings fail, there may be a howling sound while the pump is running, and shaft wear can be felt by rocking the water pump pulley up and down with the drivebelt removed. It is important not to mistake drivebelt slippage, which causes a squealing sound, for water pump bearing failure. Even if a pump shows no outward signs of a problem, such as noise or leakage, it may still need to be replaced. The only sure way to determine this is through removal for close examination. A quick check of water pump performance is to turn on the heater. If the pump is failing, it may not be able to efficiently circulate hot water to the heater core as it should.

Disconnect all hoses from the water pump and secure them out of the way.

Yes, even if a water pump shows no outward signs of a problem such as noise or leakage, it may still need to be replaced.

1. Compare the new water pump with the old one to ensure they are identical. 2. Place the gasket and water pump into position. 3. Install the new mounting bolts. 4. Tighten the water pump mounting bolts in a criss-cross pattern to the specified torque.