31312 Mercury SCREW, LATCH ASSEMBLY TO BARREL (7/8")

Illustration 1 g01181798
Schematic for the engine speed/timing sensors
Test Step 1. Check for Diagnostic Codes
Connect Cat ET to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools".
Restore electrical power to the engine ECM.
Start the engine and run the engine until the engine is at the normal operating temperature. Note: If the engine will not start, monitor the engine rpm on Cat ET while the engine is being cranked. Cat ET may need to be powered from another battery while the engine is being cranked.
Wait at least 30 seconds for activation of the diagnostic codes. Look for these codes on Cat ET:
190-02
190-11
342-02
342-11Expected Result:One or both of the diagnostic codes that are listed above are logged or active.Note: If the engine will not start and Cat ET displayed 0 rpm during cranking, select "No Engine rpm".Results:
No Engine rpm - Engine rpm is not indicated on Cat ET. Proceed to Test Step 2.
Active or logged code - There is an active diagnostic code or a logged diagnostic code for an engine speed/timing sensor. Proceed to Test Step 4.
No codes - Neither code is active or logged.Repair: Refer to the appropriate symptoms in Troubleshooting, "Troubleshooting Without a Diagnostic Code".STOPTest Step 2. Check the Installation of the Sensor Assembly
Remove electrical power from the engine ECM.
Illustration 2 g01180490
Left side view
(1) Engine
(2) Mounting flange
(3) Bracket
Visually inspect the sensor assembly without removing the sensor assembly from the engine. Flanges (2) must be flush against engine (1) in order to ensure proper operation. Inspect bracket (3). Verify that the bracket securely holds the flanges of the sensors flush against the engine.Verify that the bracket is not bent. If the bracket is bent or if an obstruction is preventing the sensor assembly from being installed correctly, the engine will not start.Note: The bracket cannot be replaced separately.
Remove the sensor assembly from the engine.
Illustration 3 g01180501
Exploded view of the engine speed/timing sensors
(4) O-ring seals
Ensure that one O-ring (4) is installed on each sensor. Check the O-rings for damage. Replace the O-rings, if necessary. Results:
OK - The sensor assembly's components are OK.Repair: Perform the following procedure in order to properly install the sensor assembly:
Lubricate each O-ring with engine oil.
Fully seat the sensor assembly in the engine. Note: If the sensor assembly will not fully seat into the engine, replace the sensor assembly.
Tighten the bracket bolt.
Connect the sensor's electrical connectors. Verify that the connectors are latched on both sides.
Ensure that the harness is properly secured, and that the tie-wraps are placed in the correct location. Proceed to Test Step 3.
Not OK - At least one of the sensor assembly's components is not OK.Repair: Obtain a new sensor assembly. Perform the following procedure in order to properly install the sensor assembly:
Lubricate each O-ring with engine oil.
Fully seat the sensor assembly in the engine. Note: If the sensor assembly will not fully seat into the engine, replace the sensor assembly.
Tighten the bracket bolt.
Connect the sensor's electrical connectors. Verify that the connectors are latched on both sides.
Ensure that the harness is properly secured, and that the tie-wraps are placed in the correct location. Verify that the problem is resolved.STOPTest Step 3. Inspect the Electrical Connectors and the Wiring
Illustration 4 g01181799
Left side engine view (typical example)
(5) J401/P401 connector for the primary engine speed/timing sensor
(6) J402/P402 connector for the secondary engine speed/timing sensor
(7) J2/P2 ECM connector
Thoroughly inspect connectors (5), (6), and (7). Refer to Troubleshooting, "Electrical Connectors - Inspect".
Illustration 5 g01181800
Left side view
(P2-48) Primary engine speed/timing sensor +
(P2-49) Primary engine speed/timing sensor -
(P2-58) Secondary engine speed/timing sensor +
(P2-59) Secondary engine speed/timing sensor -
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the engine speed/timing sensors.
Check the allen hea