GM 94853865 Belt,Water Pump & Generator

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The system consists of a belt-driven air injection pump, valves, and connecting hoses that supply controlled air to the exhaust valves and catalytic converter. This helps burn unburned exhaust gases. The diverter valve prevents backfiring during a richer mixture. On engine overrun, excess air pressure is released through the pressure relief valve. To replace and adjust the drivebelt, loosen the pump mounting bolt and adjustment bracket, then install the new belt with 1/2 inch of free-play. Replace the pump filter by compressing the belt, loosening the pulley bolts, removing the belt and pulley, and replacing the filter. Inspect and replace deteriorated hoses and tubes, using anti-seize compound on screw threads. Test the check valve by blowing through it towards the manifold. Replace the diverter valve if necessary. Remove carbon build-up from air injection tubes and replace warped or burned tubes. Check the pump operation by accelerating the engine and checking for increased airflow. Replace the pump by disconnecting hoses, removing the pulley, and removing the mounting bolts. Adjust the belt tension.