FUEL SYSTEM Engines with Serial Numbers 75V1-UP, 90N6121-UP

FUEL SYSTEM

SYSTEMS OPERATI ON

(75V1-UP, 90N6121-UP)

FUEL SYSTEM

Engines with Serial Numbers 75V1-UP, 90N6121-UP

The sleeve metering fuel system is a pressure

CAUTION: Diesel fuel is the only lubrication for

type fuel system. The name for the fuel system is

the moving parts in the transfer pump, injection

from the method used to control the amount of

pump housing, and the governor. The injection

fuel sent to the cylinders. This fuel system has an

pump housing must be full of fuel before turning

injection pump for each cylinder of the engine. It

the camshaft.

also has a fuel transfer pump on the front of the

injection pump housing. The governor is on the

rear of the injection pump housing.

This fuel system has governor weights, a thrust

collar and two governor springs. One governor

The drive gear for the fuel transfer pump is on

spring is for high idle and the other governor spring

the front of the camshaft for the injection pumps.

is for low idle. Rotation of the shaft for governor

The carrier for the governor weights is bolted to

control, compression of the governor springs,

the rear of the camshaft for the injection pumps.

movement of connecting linkage in the governor

The injection pump housing has a bearing at each

and injection pump housing controls the amount

end to support the camshaft. The camshaft for the

of fuel sent to the engine cylinders.

sleeve metering fuel system is driven by the timing

gears at the front of the engine.

Fuel from fuel tank (7) is pulled by fuel transfer

pump (11) through fuel filter (9). From fuel filter

The injection pumps, lifters and rollers, and the

(9) the fuel goes to housing for fuel injection

camshaft are all inside of the pump housing. The

pumps (14). The fuel goes in housing (14) at the

pump housing and the governor housing are full of

top and goes through inside passage (20) to fuel

fuel at transfer pump pressure (fuel system pres-

transfer pump (11).

sure).

SCHEMATIC OF FUEL SYSTEM

1. Fuel priming pump (closed position). 2. Fuel priming pump (open position). 3. Return line for constant bleed valve.

4. Constant bleed valve. 5. Manual bleed valve. 6. Fuel injection nozzle. 7. Fuel tank. 8. Fuel inlet line. 9. Fuel

filter. 10. Bypass valve for fuel priming pump. 11. Fuel transfer pump. 12. Fuel bypass valve. 13. Camshaft. 14.

Housing for fuel injection pumps. A. Check valve. B. Check valve. C. Check valve. D. Check valve.