8637679 Volvo.Penta Seal

Illustration 1 g00847122
(1) Grounding stud
(2) 40 pin connector (customer)
(3) Injection actuation pressure control valve
(4) Oil temperature sensor
(5) Oil pressure sensor
(6) Atmospheric pressure sensor
(7) Secondary speed/timing sensor
(8) Fuel temperature sensor
(9) Primary speed/timing sensor
(10) Coolant temperature sensor
(11) TC probe connector
(12) Electronic Control Module
(13) Injection actuation pressure sensor (hidden view)
(14) Turbocharger outlet pressure sensor (hidden view)
(15) Connector for the fuel pressure sensor Failure of Sensors
All Sensors
A failure of any of the sensors may be caused by one of the following malfunctions:
Sensor output is open.
Sensor output is shorted to "- battery" or "+ battery".
Measured reading of the sensor is out of specification.Atmospheric Pressure Sensor
Illustration 2 g00372751
Atmospheric pressure sensor (top view)
Top view
The atmospheric pressure sensor measures the atmospheric pressure in the crankcase. A signal is sent to the Electronic Control Module (ECM).Warning Signals
Engines may be equipped with warning signals in order to alert the operator when undesirable operating conditions occur. When a warning signal is activated, corrective measures must be made before the situation becomes an emergency.Warning signals are electrically operated. The operation of all electric warning signals utilize components that actuate switches in a sensing unit. Warning signals are set for the following parameters:
critical operating temperatures
operating pressures
operating levels
operating speedsA history of all of the engine faults is maintained in the Electronic Control Module (ECM). These faults can be either Active Codes or Logged Codes. Refer to the Operation and Maintenance Manual, "Self-Diagnostics" for the definitions of the codes.The system diagnostics can be connected to a warning signal (red lamp or buzzer). The signal will continue until the condition is corrected.A switch may be installed in the warning signal circuit in order to disable the warning signal while the engine is stopped for repairs. Ensure that the warning switch is reset after repairs have been made.Cold Start Strategy
The cold start strategy utilizes the input from the oil temperature sensor to improve starting in low temperatures. The cold start strategy helps to provide the following features:
Quicker cold starts
White smoke cleanup
Decreased deep cycling of the battery
Extended engine lifeWhen the oil temperature is below 60° C (140° F), the cold start strategy is activated. The cold start strategy deactivates under any of the following conditions:
The oil temperature reaches 60° C (140° F).
The engine has run for 14 minutes.Coolant Level Sensor
Illustration 3 g00281188
Coolant level sensor
Note: The coolant level sensor is an optional feature.The coolant level sensor is used to detect a condition when the coolant level is low. The coolant level sensor provides information to the ECM. The output from the ECM can indicate a low coolant level through a relay or a lamp. Coolant must be added to the cooling system in order to correct the condition.The electrical control system can be programmed with one of the following options:"ENABLED" - The system will monitor the input from the coolant level sensor. The system is programmed to this value when the engine is shipped by Caterpillar."DISABLED" - The system will not monitor the input from the coolant level sensor. All of the diagnostics that are associated with the coolant level sensor will be disabled.See the Operation and Maintenance Manual, "Customer Specified Parameters" for more information about programmable options.Failure of the Coolant Level Sensor
A failure of the coolant level sensor will not cause a shutdown of the engine or any horsepower change.Coolant Temperature Sensor
Illustration 4 g00368334
Coolant temperature sensor (top view)
The coolant temperature sensor monitors engine coolant temperature. This feature is used for the engine system diagnostics with an output from the ECM. The output of the ECM can indicate a high coolant temperature through a relay or a lamp.
Table 1
Coolant Temperature Sensor
Activation temperature for the high coolant temperature fault 107°C (224°F) Failure of the Coolant Temperature Sensor
The ECM will detect a failure of the coolant temperature sensor. The diagnostic lamp will warn the operator about the status of the coolant temperature sensor. A failure of the coolant temperature sensor will not cause a shutdown of the engine or any horsepower change.Direct Fuel Control
The direct fuel control allows an external governor to control the fuel delivery through the ECM. The governing strategy and the speed control strategy are disabled if the direct fuel control feature is used.Engine Oil Pressure Sensor
Illustration 5 g00368455
Engine oil pressure sensor (top view)
The engine oil pressure sensor is an absolute pressure sensor that measures the engine oil pressure in the main oil gallery. The engine oil pressure sensor detects engine oil pressure for diagnostic purposes. The engine oil pressure sensor sends a signal to the ECM.Low Oil