GEAR-COUPLING 2441522 - Caterpillar

Illustration 1 g01084606When the key switch is turned to the start position, the starter solenoid valve is electrically opened. When the starter solenoid valve is open, air will flow into the air starting motor. The air flow pneumatically engages the starter pinion with the engine flywheel ring gear.When the starter pinion is engaged, internal passages allow air to flow from the starter solenoid valve to the control passage of the starter relay valve . This air flow causes the starter relay valve to open. Air now flows from the primary air tank to the air starting motor. The air starting motor will crank the engine.When the engine is started and the key switch is released from the start position, the starter solenoid valve closes. The flow of air to the starter pinion is stopped. The gear is disengaged by a spring. This also stops air flow to the control passage of the starter relay valve . The starter relay valve closes and the air starting motor disengages.