955119 Volvo.Penta Cross recessed screw

General Information
The 3306 Vehicular Engine is part of a series of 4.75 in. (120.7 mm) bore, 6.00 in. (152.4 mm) stroke in-line engines. This book has information for the six cylinder engine.The engine has 638 cu. in. (10.5 liter) displacement. The firing order is 1, 5, 3, 6, 2, 4.The starting system is direct electric and uses a 24 volt starter motor.Engine Design
CYLINDER AND VALVE IDENTIFICATIONFuel System
FUEL SYSTEM SCHEMATIC
1. Fuel priming pump. 2. Fuel transfer pump bypass valve. 3. Fuel filter. 4. Fuel injection pump. 5. Precombustion chamber. 6. Fuel supply line. 7. Primary fuel filter. 8. Fuel transfer pump. 9. Fuel injection pump housing fuel manifold.The fuel system is a pressure type system. There is one injection pump and injection valve for each cylinder. The injection pumps are in the pump housing. The injection valves are in the precombustion chambers.The transfer pump (8) pulls fuel from the fuel tank through primary filter (7). It sends the fuel through the primary pump (1), main filter (3) and to manifold (9) of the injection pump housing. The fuel in manifold (9) of the injection pump housing goes to the injection pumps. The injection pumps are in time with the engine and send fuel to the injection valves under high pressure.Priming pump (1) is used to fill the system with fuel and to remove air from the fuel filter, fuel lines, and components.The transfer pump has a bypass valve. The bypass valve controls the maximum pressure of the fuel. The extra fuel goes back to the inlet of the pump.Fuel Injection Pump
Injection pump plungers (5) and lifters (8) are lifted by cams on camshaft (9) and always make a full stroke. The force of springs (6) hold the lifters (8) against the cams of camshaft (9).Fuel from fuel manifold (1) goes through inlet passage (2) in the barrel and then into the chamber above plunger (5). During injection, the camshaft cam moves plunger (5) up in the barrel. This movement will close inlet passage (2) and push the fuel through the fuel lines to the injection valves.The amount of fuel sent to the injection valves is controlled by turning plungers (5) in the barrels. When the governor moves fuel rack (7), the fuel rack moves gears (4) that are fastened to the bottom of plungers (5).
FUEL INJECTION PUMP
1. Fuel manifold. 2. Inlet port. 3. Check valve. 4. Gear segment. 5. Pump plunger. 6. Spring. 7. Fuel rack. 8. Lifter. 9. Camshaft.Governor Operation
The accelerator pedal is connected to the control lever on the engine governor. The governor controls the amount of fuel needed to keep the desired engine rpm.The governor has governor weights (11) driven by the engine through drive gear (7). When the engine is running, the rotation of weights (11) makes a force. The difference in the force of weights (11) and spring (4) controls the movement of valve (12). Valve (12) sends engine oil to either side of piston (13). Piston (13) will move the rack to increase or decrease fuel to the engine.When the engine load increases, engine rpm decreases. The speed of rotation of weights (11) becomes less. Weights (11) move toward each other and make less force. Governor spring (4) can move valve (12) forward. As valve (12) moves forward, oil passage (6) around valve (12) opens to pressure oil. Oil is sent through passage (6) and fills the chamber behind piston (13). The pressure oil pushes piston (13) and the rack forward. This increases the amount of fuel to the engine. Engine rpm increases until the force from the rotation of weights (11) makes a balance with the force against governor spring (4).
HYDRAULIC GOVERNOR
1. Collar. 2. Lever assembly. 3. Seat. 4. Governor spring. 5. Thrust bearing. 6. Oil passage. 7. Drive gear (weight assembly). 8. Cylinder. 9. Bolt. 10. Spring seat. 11. Weight. 12. Valve. 13. Piston. 14. Sleeve. 15. Oil passage. The governor valve is shown in the position when the force of the weights and the force of the spring are balanced.When engine load decreases, engine rpm increases. The speed of rotation of weights (11) increases. Weights (11) move apart and make more force against governor spring (4). Valve (12) moves backwards and sends the oil behind piston (13) through a drain passage, opened at the rear of piston (13). The pressure oil in the chamber between sleeve (14) and piston (13) pushes piston (13) and the rack backwards. This decreases the amount of fuel to the engine. Engine rpm decreases until the force from the rotation of weights (11) makes a balance with the force of governor spring (4).When the engine rpm is at LOW IDLE, a spring-loaded plunger in lever assembly (2) comes in contact with a shoulder on the adjustment screw for low idle. To stop the engine, pull back on the governor control. This will let the spring-loaded plunger move over the shoulder on the low idle adjusting screw and move the fuel rack to the fuel OFF position. With no fuel to the engine cylinders, the engine will stop.Oil from the engine lubrication system gives lubrication to the governor weight bearing. The other parts of the governor get lubrication from "splash-lubrication" (oil thrown by other parts). Oil from the governor runs down into the housing for the fuel injection pumps.Fuel Injection Valve
Fuel, under high pressure from the injection pumps, is sent through the fuel lines to the fuel injection valves. When the fuel under high pressure goes into the nozzle assembly, the check valve inside the nozzle opens and the fuel goes into the precombustion chamber. The injection valve changes the fuel to many very small drops of fuel. This gives the fuel the correct characteristics for good combustion.
CROSS SECTION OF THE PRECOMBUSTION CHAMBER AND FUEL INJECTION VALVE
1. Fuel injection line. 2. Nut. 3. Glow plug. 4. Body. 5. Nozzle assembly. 6. Precombustion chamber.Glow Plugs
Glow plugs are an aid for cold weather starting. During cold weather starting, the pressure in the cylinders made by the compression stroke