STARTER PINION GROUP 8M9249 - Caterpillar

Checking the Air Inlet Shutoff
The air inlet shutoff is available for certain engine ratings that operate in areas with large amounts of combustible gases. When an overspeed is detected, a relay activates the air inlet shutoff system and fuel injection is disabled. This is accomplished by closing a flap in order to cut off the air supply to the engine. Once the air inlet shutoff is activated the flap must be manually reset to the open position, before the engine can be restarted."Air Inlet Shutoff System Control Test"The "Air Inlet Shutoff System Control Test" is available to test the air inlet shutoff system. This test will determine if the air inlet shutoff system is working correctly. When the test is activated the air inlet shutoff will activate and the engine will shut down. The following conditions must be met before this test can be used:
Engine speed is 1500 rpm 100 rpm.
The transmission is in neutral.
Turn the keyswitch to the OFF position.
Connect the Caterpillar Electronic Technician (Cat ET) to the data link connector.
Turn the keyswitch to the ON position.
Place the transmission in the neutral position.
Start the engine. Increase the engine speed from low idle to 1500 rpm 100 rpm.
Access the "Air Inlet Shutoff System Control Test" in the "Diagnostic Tests" under the "Diagnostics" menu on Cat ET.
Start the test.
Wait for the engine to stop.
Stop the test.Expected ResultFuel injection is disabled. The air inlet shutoff is activated and the engine is shutdown.Result:OK: The engine is shut down when the "Air Inlet Shutoff" is activated. The air inlet shutoff is working correctly.Not OK:The engine did not shut down. Refer to Troubleshooting, "Air Inlet Shutoff Circuit - Test" for additional information.Routine Maintenance
The air inlet shutoff is intended to be placed in a clean air stream. On some occasions, dirt, grease, oil, or carbon residue can come in contact with the device. Debris such as dirt, grease, oil, and carbon residue may impede the operation of the air inlet shutoff. Since the air inlet shutoff is intended for emergency use it is important to perform regular routine maintenance on the air inlet shutoff. Routine maintenance of the air inlet shutoff will ensure that the air inlet shutoff will function properly in an emergency situation. An appropriate log should be maintained. When the air inlet shutoff has shut down the engine, perform the following procedures.
Manually open the gate of the shutoff.
Manually close the gate of the shutoff.Manually operating the gate will remove any deposits of debris that may interfere with the proper operation of the air inlet shutoff.Parts that are Required for the Installation of the Air Inlet Shutoff
Table 3
Qty     Part Number     Part Name    
1     226-4752     Air Shutoff Gp    
2     248-4841     Band Clamp    
2     6V-6353     O-Ring Seal    
1     243-2316     Adapter    
1     203-0351     Air Elbow    
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