1975 Datsun 280z FSM - Spooled up Racing

Engine Fuel
Fig. EF-20 Dropping resistor
The dropping resistor is provided to
reduce electric current flowing
through the injector and control unit.
10. Fuel pump
The fuel pump is mounted near the
Fuel pump operation chart
fuel tank and right rear wheel. The
pump employs a wet type construction
where a vane pump with roller is
directly coupled to a motor filled with
fuel. This construction provides
superior coupling characteristics between
the pump and motor, and
greater safety in case of fire.
The relief valve in the pump is
designed to open when the pressure in
the fuel line rises over 3 to 4.5 kg/cm
(43 to 64 psi) due to trouble in the
pressure system.
The check valve prevents abrupt
drop of pressure in the fuel pipe when
stopping the engine.
When the ignition switch is turned
to the START position for cranking
operation, the fuel pump is actuated
irrespective of the position of the air
flow meter contact point. After starting
the engine (the ignition switch is
ON), the air flow meter contact turns
ON through rotation of the engine,
thereby actuating the fuel pump. If
engine stalls for some reason, the air
flow meter contact is turned OFF, and
the fuel pump is stopped, though the
ignition switch remains in the ON
position. In this manner, fuel supply is
cut off for safety purposes when the
engine accidentally stops during
driving.
OFF
IGN. SW. Position
ON
Start
A.F.M. Contact Points
Fuel Pump
-
-
X
OFF
Actuated
-
X
-
ON
Actuated
-
X
-
OFF
Unactuated
X
-
-
ON
Unactuated
X
-
-
OFF
Unactuated
X: IGN. SW. positions
Outlet
Normal flow
Relief valve actuated due to
clogged discharge line.
Inlet
1 Motor
2 Pump
3 Relief valve
4 Check valve
EF314
Fig. EF-21 Sectional view of fuel pump
EF-15