853352 Mercury COVER

Illustration 1 g00326432
Test harness for low oil pressure (A) Socket A of 8T-8730 Connector Socket. (B) Socket B of 8T-8730 Connector Socket . (C) Socket C of 8T-8730 Connector Socket . (R) 1000 Ohm ten turn potentiometer.Note: Socket C of 8T-8730 Connector Socket (C) connects to the wiper of the potentiometer (R) .This procedure enables the service personnel to verify that the protection for low engine oil pressure is functioning. This procedure controls the oil pressure signal to the module for pressure and temperature without affecting the engine lubrication system. Engine shutdown and the alarm are verified at idle speed and rated speed.Note: If equipped, the fault indicator for low oil pressure and the horn on an alarm module will activate at 34 kPa (5 psi) above the value for engine shutdown.The trip conditions for a shutdown that is caused by low oil pressure at idle speed are listed below.
The engine speed is less than the value for oil step speed.
The engine oil pressure is less than the value which will cause a shutdown for oil pressure at idle speed.The trip conditions for a shutdown that is caused by low oil pressure at rated speed are listed below:
The engine speed is greater than the value for oil step speed.
The engine oil pressure is less than the value which will cause a shutdown for oil pressure at rated speed.
Determine the programmed Status Control Module (SCM) setpoint for: oil step speed, shutdown for oil pressure at idle speed and shutdown for oil pressure at rated speed
Turn the Engine Control Switch (ECS) to the OFF/RESET position.
Disconnect the connector for the engine oil pressure sensor from the engine harness. Connect the test harness to the engine harness.
Turn the ECS to the AUTO position. Monitor the engine oil pressure on the SCM display. Adjust potentiometer (R) until the pressure that is displayed is greater than the value which will cause a shutdown for oil pressure at idle speed, but less than 345 kPa (50 psi).Note: The SCM displays an 09 "dIAG" code, when the oil pressure is greater than 345 kPa (50 psi) and the engine is NOT running. If necessary, clear the 09 code. To clear the diagnostic code, decrease the sensed oil pressure by adjusting potentiometer (R). Turn the ECS to the OFF/RESET position.
Start and run the engine at idle speed. Keep the engine speed below the setpoint for the oil step speed.
Lower the oil pressure that is displayed on the SCM by slowly adjusting potentiometer (R) .Note: The engine shuts down when the oil pressure falls below the setpoint for the oil pressure at idle speed .
Verify that the engine shuts down when the oil pressure falls below the setpoint for the oil pressure at idle speed. Verify that the fault indicator for the low oil pressure on the SCM is flashing.Note: The fault indicator for the low oil pressure will activate prior to the engine shutdown. The fault indicator for the horn on the alarm module will activate prior to the engine shutdown.
Turn the ECS to the OFF/RESET position.
Turn the ECS to the AUTO position. Monitor the engine oil pressure on the SCM display. Adjust the potentiometer (R) until the pressure that is displayed is less than the value which will cause a shutdown for oil pressure at rated speed, but less than 345 kPa (50 psi).Note: The SCM displays an 09 "dIAG" code, when the sensed oil pressure is greater than 345 kPa (50 psi) and the engine is not running. If necessary, clear the 09 code. To clear the diagnostic code, decrease the sensed oil pressure by adjusting potentiometer (R). Turn the ECS to the OFF/RESET position.
Start and run the engine at rated speed. Keep the engine speed above the set point for oil step speed.
Lower the oil pressure that is displayed on the SCM by slowly adjusting potentiometer (R) .Note: The engine shuts down when the oil pressure is below the set point for the rated speed.
Verify that the engine shuts down when the oil pressure falls below the set point for the oil pressure at rated speed. Verify that the indicator for the low oil pressure on the SCM is flashing.Note: The indicator for the low oil pressure and the horn on an alarm module will activate prior to engine shutdown.
Turn the ECS to the OFF/RESET position in order to clear the SCM.
Remove the test harness. Reconnect the engine oil pressure sensor to the engine harness.
Table 1
"Relay Logic Chart for the Gas Engine Status Control Panel "    
Relay
Number
(3E-7573)     Function     Cranking     Crank
Termination     Low Pressure
Setpoint     Run     Fault
Shutdown     Normal
Shutdown
Cooldown
/Off     Comments    
K1     2301 Ramp     D     D     E     E     D     E/D     Energized above Low Oil Pressure Setpoint    
K2     ENFR     D     D     D     D     E     D/D     Energized by a Fault
Clear with the Reset    
K3     CTR     D     E     E     E     D     E/D     Energized above RPM for Crank Termination
De-energized at zero RPM plus 2 seconds    
K4     SMR     E     D     D     D     D     D/D     ETC
Locked out until zero RPM
All Faults reset.    
K5     RR     E     E     E     E     D     E/D     ETR
De-energize at the request for engine shutdown.    
K6     MGR/MSR     E     E     E     E     D or E     E/E     E for normal operation if engine is being asked to start (ECS in Run or Auto with IC contact closed). De-energized for emergency shutdown (see below) Contact will be re-energized 10 to 15 seconds after reaching zero RPM if engine is being asked to start.    
K7     FCR/ETR     E     E     E     E     D     E/D     ETR
De-energized to Shutdown    Emergency conditions are listed below:
Overspeed
Emergency Stop Push button
Diagnostic Codes 1, 4, 6
All six fault indicators illuminated.CTR - "Crank Termination