959265 Volvo.Penta Hex. socket screw

Engine Design
CYLINDER AND VALVE LOCATIONBore ... 5.40 in.(137.2 mm)Stroke ... 6.50 in.(165.1 mm)Number and Arrangement of Cylinders ... 6, In LineFiring Order (Injection Sequence) ... 1, 5, 3, 6, 2, 4No. 1 Cylinder Location ... FrontRotation of Crankshaft (when seen from flywheel end) ... counterclockwiseRotation of Fuel Pump Camshaft (when seen from pump drive end) ... counterclockwiseFuel System
FUEL SYSTEM
1. Injection valve. 2. Anti-siphon block. 3. Injection pump housing. 4. Priming pump. 5. Plug. 6. Secondary filter. 7. Fuel line. 8. Return line to tank. 9. Fuel tank. 10. Primary filter. 11. Transfer pump.This engine has a pressure type fuel system. There is a single injection pump and injection valve (1) for each cylinder. The injection pumps are in the pump housing (3) on the left side of the engine. The injection valves (1) are in the precombustion chambers or adapters under the valve cover.The transfer pump (11) pulls fuel from the fuel tank (9) through the primary filter (10) and sends it through the base of priming pump (4) and the secondary filter (6), through the anti-siphon block (2) and to the manifold of the injection pump housing. When priming pump (4) is not used, the position of fuel line (7) and plug (5) are reversed. The fuel in the manifold 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.Some of the fuel in the manifold is constantly sent back through the anti-siphon block (2) and through the return line (8) to the fuel tank to remove air from the system. Orifices in the anti-siphon block control the amount of fuel that goes back to the fuel tank.The priming pump (4) is used to remove air from the fuel filter, fuel lines and components.The transfer pump has a bypass valve and a check valve. The bypass valve (lower side) gives control to the pressure of the fuel. The extra fuel goes to the inlet of the pump.Fuel Injection Pump Operation
Injection pump plungers (4) and lifters (8) are lifted by cams on camshaft (9) and always make a full stroke. The force of springs (5) hold the lifters (8) against the cams of the camshaft.Fuel from fuel manifold (1) goes through inlet passage (2) in the barrel and then into the chamber above plunger (4). During injection, the camshaft cam moves plunger (4) up in the barrel. This movement will close inlet passage (2) and push the fuel out through the fuel lines to the injection valves.The amount of fuel sent to the injection valves is controlled by turning plunger (4) in the barrel. When the governor moves fuel rack (7), the fuel rack moves gear (6) that is fastened to the bottom of plunger (4).
CROSS SECTION OF THE HOUSING FOR THE FUEL INJECTION PUMPS
1. Fuel manifold. 2. Inlet passage in pump barrel. 3. Check valve. 4. Pump plunger. 5. Spring. 6. Gear. 7. Fuel rack. 8. Lifter. 9. Camshaft.Fuel Injection Valve
Fuel, under high pressure from the injection pumps, is sent through the injection lines to the injection valves. The injection valves change the fuel to the correct fuel characteristic (spray pattern) for good combustion in the cylinders.The fuel injection valves are installed in the precombustion chambers in engines equipped with precombustion chambers. An adapter takes the place of the precombustion chamber in engines equipped with direct injection. The precombustion chambers or adapters are installed in the cylinder heads.Hydra-Mechanical Governor
The accelerator pedal, or governor control, 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 is driven by the engine and has governor weights (12), governor spring (5), valve (14) and piston (15). The valve and piston are connected to fuel rack (18). The pressure oil for the governor comes from the engine oil pump. Pressure oil goes through passage (17) and around sleeve (16). The accelerator pedal, or governor control, controls only the compression of governor spring (5). Compression of the spring always pushes to give more fuel to the engine. The centrifugal force (rotation) of governor weights (12) is always pulling to get a reduction of fuel to the engine. When these two forces are in balance, the engine runs at the desired rpm (governed rpm).
HYDRA-MECHANICAL GOVERNOR (Typical Example Shown at Full Load Condition)
1. Collar. 2. Speed limiter plunger. 3. Lever assembly. 4. Seat. 5. Governor spring. 6. Thrust bearing. 7. Oil passage. 8. Drive gear (weight assembly). 9. Cylinder. 10. Bolt. 11. Spring seat. 12. Governor weights. 13. Spring. 14. Valve. 15. Piston. 16. Sleeve. 17. Oil passage. 18. Fuel rack.Governor valve (14) is shown in the position when the force of the governor weights and the force of the governor spring are in balance.When there is an increase in engine load, there will be a decrease in engine rpm and the rotation of governor weights (12) will get slower. (The governor weights will move toward each other.) Governor spring (5) moves valve (14) forward (toward the right in picture shown). When valve (14) moves forward, an oil passage around valve (14) opens to pressure oil. Oil now flows through passage (7) and fills the chamber behind piston (15) (the rear end of the valve stops oil flow through