814684 Volvo.Penta Protective helmet

Electrical System
Wiring Diagrams
Pilot Panel Wiring Schematic (3116 & 3126 Engines) Engine and Junction Box (3116 Engine)
Wiring Diagram Notes
Only one fuel shutoff solenoid will be installed on the engine. Only the wires for the installed solenoid will be provided.Component shown dashed is located in the junction box.
Junction Box Diagram (3116 Engine 7E1330 Wiring Diagram)
Engine Diagram (3116 Engine 7E1330 Wiring Diagram)
Engine Diagram (3116 Engine 113-1100 Wiring Diagram)
Junction Box Diagram (3116 Engine 113-1100 Wiring Diagram)Engine and Junction Box (3126 Engine)
Wiring Diagram Notes
Only one fuel shutoff solenoid will be installed on the engine. Only the wires for the installed solenoid will be provided.Component shown dashed is located in the junction box.
Junction Box Diagram (3126 Engine)
Engine Diagram (3126 Engine)Components
Water Temperature Contactor
A water temperature contactor switch is located in the cooling system. This unit is non-adjustable. Thermal expansion of the element operates a micro-switch that signals an alarm on the pilot panel. The water temperature element must be in contact with the coolant. After an overheated engine is allowed to cool, the contactor automatically resets itself.Oil Pressure Switch
An oil pressure switch is located in the oil system. This switch has three terminals and serves a dual purpose. One use of this switch is to power the hour meter after the engine oil pressure reaches normal operating pressure. The other use is to signal an alarm on the pilot panel when engine oil pressure drops below the desired oil pressure.Control Relay
This is a standard type relay that, when energized, has contacts that open across one circuit and close across another circuit. The circuits are wired so that when the relay is energized voltage from the battery will go to and energize the fuel shutoff solenoid (on engines equipped with an energize to run type of solenoid). On engines which use a latching type (energize to shutoff) fuel solenoid, the control relay is de energized and voltage flows from the battery to the STOP terminal on the fuel shutoff solenoid. This in turn shuts down the engine.Electrical Indicators And Sending Units
The electrical indicators and sending units operate in electrical balance. Because of this, the voltage and resistance ratings are important to get the correct indications on the indicators.Water Temperature Sending Unit
Sending Unit for Water Temperature
(1) Bulb. (2) Nut. (3) Connection.The sending unit for water temperature is an electrical resistance. It changes the value of its resistance according to the temperature which the bulb (1) feels.The sending unit is in a series circuit with the electrical indicator. When the temperature is high, the resistance is low. This makes the indicator have a high reading.The sending unit must be in contact with the coolant. If the coolant level is too low because of a sudden loss of coolant while the engine is running or because the level is too low before starting the engine, the sending unit will not work correctly.Pressure Sending Unit
Sending Unit for Pressure
(1) Connection. (2) Fitting.The sending unit for pressure is an electrical resistance. It has a material which changes electrical resistance according to pressure which it feels.The sending unit for pressure is in a series circuit with the electrical indicator. As the pressure on the sending unit changes, the reading on the indicator changes in the same way.Fuel System
Fuel Cooler (If Equipped)
Location Of Fuel Cooler (Left Side View)
(1) Fuel return fitting. (2) Return to cooler line. (3) Fuel cooler.The fuel cooler (3) may be used in a marine application. The fuel cooler helps reduce the heat felt in a cabin because the fuel tank may be located close to an interior wall or in the floor. Additionally, the fuel cooler (3) is used to help control fuel temperatures, which when elevated can result in reduced overall engine performance. Fuel coolers (3) are recommended for applications where fuel tanks are small and/or where engines are operated for long periods of time with lower fuel levels.When an engine is equipped with a fuel cooler (3) then the excess fuel that is not burned in the combustion process is routed from the engine through the fuel return to cooler line (2) to the fuel cooler (3). The hot fuel passes through the core portion of the fuel cooler (3) which is surrounded by the water being pulled into the sea water/separate circuit water pump. Once the fuel passes through the core it is returned to the fuel tank through a line attached to fuel return fitting (1). The fuel cooler group can not be used on the 3116, 3126 Keel Cooled Engines.Air Inlet Heater (3126)
To aid starting and prevent white smoke emission at start up, the Caterpillar 3126 Marine Engines are equipped with an electric heater located at the air inlet casting. Under the proper conditions of jacket water temperature, oil pressure, ignition position, and elapsed time, an electronic control module switches the heater system on. The system is capable of delivering heat for thirty seconds prior to start up, during cranking, and up to five minutes continuous and fifteen minutes of cycling (ten seconds on, ten seconds off) after the engine has started.If for any reason the air inlet heater system malfunctions, the engine will start and run. The only concerns may be the amount of "white smoke" present and the possible need to use an alternative starting aid.System Components
The basic components of the air inlet heater system are: Magnetic switch, heater element, coolant temperature switch, electronic control module, oil pressure switch, and an indicator lamp.
Location Of Components
(1) Control module. (2) Magnetic switch.
Location Of Components
(3) Inlet manifold. (4) Air inlet heater. (5) Oil pressure switch. (6) Aftercooler. (7) Coolant temperature switch. (8) Water temperature regulator housing.The magnetic switch is normally located in the junction box. It turns the 12V (or 24V) heater ON and OFF in response to signals from heater control module (1).The air inlet heater (4) is located between the inlet manifold (3) and aftercooler (6). The center terminal is positive, the front and rear terminals are negative. The negative