Fuel Pump - Jeep 1979 CJ-5 Technical & Service Manual

FUEL SYSTEMS 1J-7
FUEL T A N K
F U E L F I L T E R
FROM
F U E L PUMP
J 4 3 1 8 5
Fig. 1 J - 1 1 Fuel Vapor Return System—Typical
The check valve uses a stainless steel, spring-assisted
check ball to close the orifice (fig. 1J-12). It is mounted in
the fuel return line at the fuel filter and is secured by a
clamp. Pressure of from 0.1 to 0.6 psi (.68 to 4.13 kPa) at
the fuel filter side opens the check valve and permits
normal operation of the fuel return system.
The check valve is marked with an arrow in the direc-
tion of flow. If it is reversed, the fuel return system will
not operate.
FUEL GAUGE
Refer to Chapter 1L—Power Plant Instrumentation
for Operation, Diagnosis and Replacement. Service of
the sending unit is covered under Fuel Tank in this
chapter.
FUEL PUMP
A single-action, stamped fuel pump is used for all
engine applications.
The fuel pump consists of an actuating lever, a dia-
phragm and spring, an inlet valve and an outlet valve
(fig. 1J-13). An eccentric on the engine camshaft oper-
ates the fuel pump lever which is linked to the pump
diaphragm . The lever pulls the diaphragm to its ex-
tended position, drawing fuel through the inlet valve.
Spring pressure pushes the diaphragm toward its re-
laxed position, forcing fuel out through the outlet valve.
FROM
FUEL
FILTER
SPRING
— - N O
o o o o o o o o o
o o o o o o o o o
FUEL R E T U R N
LINE TO FUEL
T A N K
6 0 2 7 8
Fig. 1 J - 1 2
In-Line Check Valve