1276467 Volvo.Penta Screw

Fuel System
Engine Design
Bore ... 4.75 in. (120.7 mm)Stroke ... 6.0 in.(152.4 mm)Number of Cylinders ... 4Cylinder Arrangement ... *in-lineFiring Order (Injection Sequence) ... 1, 3, 4, 2Direction of Rotation (when seen from flywheel end) ... Counterclockwise
CYLINDER AND VALVE IDENTIFICATION*No. 1 Cylinder Is Opposite Flywheel End. Introduction
The Sleeve Metering Fuel System is a pressure type fuel system. The name for the system is from the method used to control the amount of fuel in the fuel injection charge. This system has an injection pump and an injection valve for each cylinder. The injection pumps are in the fuel injection pump housing on the right side of the engine. The injection valves are in the precombustion chambers in the cylinder head.The drive gear for the fuel transfer pump is on the front of the camshaft for the injection pumps. The carrier for the governor weights is bolted to the rear of the camshaft for the injection pumps. The injection pump housing has a bearing at each end to support the camshaft. The camshaft for the sleeve metering fuel system is driven by the timing gears at the front of the engine.The injection pumps, lifters and rollers, and the camshaft are all inside of the pump housing. The pump housing and the governor housing are full of fuel at transfer pump pressure (fuel system pressure).
Diesel fuel is the only lubrication for the moving parts in the transfer pump, injection pump housing and the governor. The injection pump housing must be full of fuel before turning the camshaft.
Fuel System Timing
Injection timing before TC (top center) is 13° 30" 1°Fuel Injection Valves
Fuel, under high pressure from the injection pumps, is sent through the injection valves. The injection valves change the fuel to the correct fuel characteristics (spray pattern) for good combustion in the cylinders.The fuel injection valves are installed in the precombustion chambers. The precombustion chambers are installed in the cylinder head.Water Separator
Some engines have a water separator. The water separator is installed between the fuel tank and the rest of the fuel system. For efficiency in the action of the water separator, the fuel flow must come directly from the fuel tank and through the water separator. This is because the action of going through a pump or valves before the water separator lowers the efficiency of the water separator.The water separator can remove 95% of the water in a fuel flow of up to 33 gph (125 liter/hr) if the concentration of the water in the fuel is 10% or less. It is important to check the water level in the water separator frequently. The maximum amount of water which the water separator can hold is 0.8 pt (0.4 liter). At this point the water fills the glass to 3/4 full. Do not let the water separator have this much water before draining the water. After the water level is at 3/4 full, the water separator loses its efficiency and the water in the fuel can go through the separator and cause damage to the fuel injection pump.Drain the water from the water separator every day or when the water level gets to 1/2 full. This gives the system protection from water in the fuel. If the fuel has a high concentration of water, or if the flow rate of fuel through the water separator is high, the water separator fills with water faster and must be drained more often.To drain the water separator, open the valve in the drain line and the valve at the top of the water separator. Let the water drain until it is all out of the water separator. Close both valves.
WATER SEPARATORFuel Flow With Engine Running
System With Siphon Break
SCHEMATIC OF FUEL SYSTEM
1. Governor housing. 2. Fuel injection pump. 3. Fuel injection pump housing. 4. Bypass valve. 5. Bleed valve. 6. Fuel tank. 7. Check valve. 8. Fuel supply line. 9. Water separator (if so equipped). 10. Drain valve. 11. Vent valve. 12. Fuel filter. 13. Check valve. 14. Priming pump. 15. Check valve. 16. Fuel transfer pump. A. Siphon break orifice.
FUEL SYSTEM INSTALLED
2. Fuel injection pump. 5. Bleed valve. 8. Fuel supply line. 12. Fuel filter. 14. Priming pump.
GOVERNOR AND FUEL INJECTION PUMP
1. Governor housing. 3. Fuel injection pump housing. 16. Fuel transfer pump.When the engine is running fuel transfer pump (16) pulls fuel from fuel tank (6) through fuel supply line (8). The fuel goes through water separator (9) (if so equipped), fuel filter (12) and into channel (17) behind cover (18).
FUEL INJECTION PUMP HOUSING COVER
14. Priming pump. 17. Channel. 18. Cover.From channel (17) the fuel goes through priming pump (14) into passage (D) to the fuel transfer pump (16).
FUEL INJECTION PUMP HOUSING
4. Bypass valve. 7. Check valve. D. Passage to fuel transfer pump.From fuel transfer pump (16) fuel under pressure fills fuel injection pump housing (3). Pressure of the fuel in housing (3) is controlled by bypass valve (4). Pressure of the fuel at full load is 30 5 psi (205 35 kPa). If the pressure of the fuel in housing (3) gets too high, bypass valve (4) will move (open) to let some of the fuel return to the transfer pump (16).Fuel injection pumps (2) send fuel, under high pressure, out of housing (3) into the fuel injection lines during injection. The fuel goes through the lines to the fuel injection valves in the precombustion chambers.Fuel Flow Using The Priming Pump And Bleed Valve
When the priming pump handle is pulled out, negative air pressure in the pump makes check valve (13) open and pulls fuel from the tank. Pushing the handle in closes check valve (13) and opens check valve (15). This pushes air and/or fuel into the housing through passage (19) and check valve (7). More operation of the priming pump will pull fuel from the tank until fuel supply line (8), fuel filter (12) and housing (3) are full of fuel. At this time the fuel flow from the bleed valve (5) will have no air