0432987 JOHNSON CARBURETOR AY

The Engine Timing Actuator control system will dynamically adjust cam position to optimize engine performance and mitigate detonation.The Engine ECM will command a desired cam position based on the current operating conditions.When an error occurs between the commanded cam position and actual cam position, diagnostic codes 635-7 or 1245-7 are activated.If detonation occurs during the time of the cam position error, a supporting code of 635-14 or 1245-14 is activated.Is important to resolve any Engine Timing Actuator Not Responding faults prior to troubleshooting engine detonation.If detonation occurs after a complete resolution of either the 635-7 or 1245-7 , refer to Troubleshooting, Detonation Occurrence.Troubleshoot any of the following associated codes prior to beginning this procedure:
Table 2
Associated Codes
635-5
Engine Timing Actuator #1 : Current Below Normal
635-6
Engine Timing Actuator #1 : Current Above Normal
1245-5
Engine Timing Actuator #2 : Current Below Normal
1245-6
Engine Timing Actuator #2 : Current Above Normal
100-1
Engine Oil Pressure : Low - most severe (3)
100-17
Engine Oil Pressure : Low - least severe (1)
Table 3
Troubleshooting Test Steps Values Results
1. Check for Codes
A. Connect Cat® Electronic Technician (ET) to the service tool connector.
B. Determine if a code is active or logged.
Codes
Result: A 635-7 or a 1245-7 code is active or logged.
Proceed to Test Step 2.
2. Inspect the Electrical Connectors and the Wiring
A. Turn the main disconnect switch to the OFF position.
B. Thoroughly inspect the connectors. Refer to Troubleshooting, "Electrical Connectors-Inspect" for additional information.
C. Perform a 45 N (10 lb) pull test on the connector wires.
D. Check the harness for abrasions and pinch points.
Connectors and Wiring
Result: The connectors and wiring appear to be OK.
Proceed to Test Step 3.
Result: There is a problem with the connectors and/or wiring.
Repair: Repair or replace the connectors or wiring. Ensure that all the seals are properly in place and ensure that the connectors are coupled.
If the problem is not resolved, proceed to Test Step 3.
3. Check the Timing Actuator Solenoid Valve Installation
A. Check the torque on the solenoid valve lock nut to be 54 N m (40 lb ft).
B. Check the torque on the solenoid valve coil lock nut to be 27 N m (20 lb ft)
Torque
Result: Both solenoid valve lock nuts were properly torqued to specification.
Proceed to Test Step 4.
Result: One or both of the solenoid valve lock nuts were not properly torqued to specification.
Repair: Properly torque the lock nuts. Run the engine at loads > 50% to verify the repair.
If the problem is not resolved, proceed to Test Step 4.
4. Remove and Inspect Engine Timing Actuator Solenoid Valve
A. Turn the main disconnect switch to the OFF position.
B. Disconnect the solenoid valve from the wiring harness and remove the solenoid valve from the timing actuator assembly.
C. Check the solenoid valve for any obvious signs of damage.
Solenoid Valve
Result: The solenoid valve appears to be OK.
Proceed to Test Step 5.
Result: The solenoid valve appears to be damaged.
Repair: Replace the solenoid valve. Run the engine at loads > 50% to verify the repair.
If the problem is not resolved, proceed to Test Step 5.
5. Interchange the Locations of the Engine Timing Actuator Solenoid Valves
A. Turn the main disconnect switch to the OFF position.
B. Move the left actuator solenoid valve to the right side and move the right actuator solenoid valve to the left side.
C. Run the engine under the same conditions that the code occurred.
Solenoid Valve
Result: The problem did not follow the engine timing actuator solenoid valve to the opposing bank.
Proceed to Test Step 6.
Result: The opposing bank now has an active diagnostic code. The problem followed the engine timing actuator solenoid valve.
Repair: Replace the engine timing actuator solenoid valve.
If the problem is not resolved, proceed to Test Step 6.
6. Inspect Engine Timing Actuator Assembly
A. Turn the main disconnect switch to the OFF position.
B. Remove the cam cover and inspect timing actuator assembly for damage to the following:
- Gear
- Hub assembly
- Sealing rings
Timing actuator assembly
Result: No damage to the gear, hub assembly, or sealing rings was found.
Proceed to Test Step 7.
Result: Damage to the gear, hub assembly, or sealing rings was found.
Repair: Repair or replace the damaged components. Run the engine at loads > 50% to verify the repair.
If the problem is not resolved, proceed to Test Step 7.
7. Interchange the locations of the Engine Timing Actuator Assemblies
A. Turn the main disconnect switch to the OFF position.
B. Move the left actuator assembly to the right side and the right actuator assembly the left side.
C. Run the engine under the same conditions that the code occurred.
Timing actuator assembly
Result: The opposing bank now has an active diagnostic code. The problem followed the engine timing actuator assembly.
Repair: Replace the engine timing actuator assembly.
If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).