5007631 EVINRUDE *GEAR SET, Fwd, Pinion

SCHEMATIC OF THE FUEL SYSTEM
1. Fuel priming pump. 2. Fuel transfer pump. 3. Fuel injection pump. 4. Precombustion chamber. 5. Fuel supply line. 6. Primary fuel filter. 7. Bypass valve for fuel transfer pump. 8. Air vent valve. 9. Fuel filters. 10. Fuel manifold.This engine has a pressure type fuel system. There is a single injection pump and injection valve for each cylinder. The injection pumps (3) are in the pump housing on the right side of the engine. The injection valves are in the precombustion chambers (4) in the top left side of the cylinder head.The transfer pump (2) sends fuel from the fuel tank to the primary fuel filter (6). The primary fuel filter (6) removes the larger dirt particles from the fuel. Fuel goes from the primary fuel filter (6) to the fuel filters (9). The fuel filters (9) remove the smaller dirt particles from the fuel. Fuel goes from the fuel filters (9) to the fuel manifold (10) in the pump housing. This manifold is the source of fuel supply for each injection pump (3). The injection pumps (3) send fuel through high pressure fuel 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 transfer pump (2) can supply more fuel than is necessary for injection, so a bypass valve (7) is used to control the pressure of the fuel in the fuel system.An air vent valve (8) in the fuel system is used to remove air from the fuel system. Air is removed by opening the air vent valve and putting pressure to the fuel system with the priming pump (1). Put pressure to the fuel system until a flow of fuel, free of air bubbles, comes from the vent line.Fuel Injection Pump Operation
Injection pump plungers (3) and lifters (6) are lifted by cams on camshaft (7) and always make a full stroke. The force of springs (5) hold the lifters (6) 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 (3). During injection, the camshaft cam moves plunger (3) 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 (3) in the barrel.
CROSS SECTION OF THE HOUSING FOR THE FUEL INJECTION PUMPS
1. Fuel manifold. 2. Inlet passage in pump barrel. 3. Pump plunger. 4. Gear segment. 5. Spring. 6. Lifter. 7. Camshaft.When the governor moves the fuel rack, the fuel rack moves gear segment (4) that is fastened to the bottom of plunger (3).Mechanical Governor
MECHANICAL GOVERNOR-LEFT SIDE VIEW (Typical Example)
1. High idle adjustment screw. 2. Low idle adjustment screw. 3. Stop. 4. Roller. 5. Spring. 6. Plunger. 7. Adjustment screw. 8. Lower housing. 9. Oil passage. 10. Weight. 11. Governor drive spindle.The governor control, is connected to the control lever on the engine governor. The governor controls the amount of fuel needed to keep the engine at the desired rpm.The governor has weights (10), which are driven by the engine. The force of the weights (10) on sleeve (14), bearing (13) and cage (12), puts force against force of spring (5). These two forces move the fuel rack through lever (15) to control the engine rpm.The 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 weights (10) 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).
MECHANICAL GOVERNOR (FRONT VIEW)
5. Spring. 7. Adjustment screw. 8. Lower housing. 10. Weight. 11. Governor drive spindle. 12. Cage. 13. Bearing. 14. Sleeve assembly. 15. Lever.When the load on the engine goes up, there is a reduction in engine rpm and the rotation of governor weights (10) will get slower. (The governor weights will move toward each other). Governor spring (5) moves the rack by way of bearing (13), cage (12) and lever (15) to give the engine more fuel.Engine rpm goes up until rotation of the governor weights is fast enough to be in balance with the force of the governor spring.When there is a reduction in engine load, there will be an increase in engine rpm and the rotation of governor weights (10) will get faster. This will move lever (15) and it pushes the fuel rack, by way of bearing (13), cage (12) and lever (15). There is now a reduction in the amount of fuel to the engine. Engine rpm goes down until the centrifugal force (rotation) of the governor weights is in balance with the force of the governor spring. When these two forces are in balance, the engine will run at the desired rpm (governed rpm).When engine rpm is at LOW IDLE, a spring-loaded plunger (6) comes in contact with the bottom of roller (4) 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 roller on the low idle adjusting screw.Oil from the engine enters the governor through passage (9) and gives lubrication to the governor flexible spindle (11) and upper parts of the governor. The upper parts of the governor get lubrication from "splash-lubrication" (oil thrown by other parts). Oil from the governor runs back into the timing gear housing through an oil return hole at the rear of the drive housing for the governor.Hydra-Mechanical Governor
An oil pump gear (10), part of shaft assembly (11), provides immediate pressure oil for the servo portion of the governor. A sump in body assembly (12) provides immediate supply for the pump. A bypass valve (B), in the body assembly, maintains correct pressure for servo supply oil.When the engine is operating,