Dodge ram truck 3500 1996 Service Manual page 1311

B R FUEL SYSTEM 14 - 77
D I A G N O S I S A N D T E S T I N G (Continued)
FUEL TRANSFER PUMP PRESSURE/CAPACITY
TEST
For operation of the fuel transfer pump primer button,
refer to Fuel Transfer Pump in the Fuel Delivery—Diesel
Engine section of this group.
The fuel transfer pump is located on the left side of
the engine and above the starter motor (Fig. 16).
FUEL T E M P E R A T U R E SENSOR
OUTPUT PRESSURE TEST
(1) Remove the clamp bolt retaining the fuel drain
manifold line to the cylinder head (Fig. 17).
ELECTRI C AL
CONNECTOR
FUEL
H E A T E R
FUEL
TRANSFER
PUMP
J9414-94
Fig. 16 Fuel Transfer Pump Location
An improperly operating fuel transfer pump can
cause low engine power and/or hard engine starting.
Inspect the fuel supply line to the pump for restric­
tions, kinks or leaks.
Fuel leaking from the weep hole in the pump cas­
ing indicates a leaking pump. The transfer pump
must then be replaced or rebuilt.
Do not operate the fuel system with a fuel line or
component suction restriction of more than approxi­
mately 100 M M Hg (4.0 inch Hg).
Low transfer pump output can be caused by a worn
eccentric on the engine camshaft.
The maximum allowable fuel pressure drop across the
fuel filter/water separator is 35 kPa (5 psi). As the filter
removes contaminants in the fuel, the pressure drop
across the fuel filter/water separator will increase. Fre­
quent replacement of the filter may indicate a worn
transfer pump. The filter/separator can be checked with a
fuel pressure gauge. For test procedures, refer to Fuel
Filter/Water Separator Tests in this section of the group.
Refer to Group 0, Lubrication and Maintenance at
the front of this manual for recommended replace­
ment intervals.
J 9 5 1 4 - 6 8
Fig. 17 Fuel Line Fittings
(2) Remove the rear banjo fitting bolt at the inlet
line (Fig. 17).
(3) Position the fuel drain manifold line (Fig. 17)
to the rear.
(4) Install and tighten special adapter tool 6829
into the top of the fuel inlet line (Fig. 18).
(5) Install a 0-60 or 0-100 psi fuel pressure gauge
to adapter tool 6829 (Fig. 18).
(6) Start engine and record fuel pressure. Mini­
mum pressure should be 172 kPa (25 psi) at rated
speed.
(7) I f fuel pressure falls below specifications, test
for fuel line inlet restrictions and overflow valve
operation before condemning the fuel transfer pump.
Proceed to step (a).
(a) Remove the rubber fuel hose and clamps
located between the fuel heater and fuel transfer
pump (Fig. 19).
(b) Install special hose adapter tool 6837
between the disconnected fittings on the heater
and transfer pump (Fig. 20). Install clamps to hose
tool 6837.