Dodge RAM TRUCK 1500 1995 Service Manual page 1189

GENERAL DIAGNOSIS—DIESEL ENGINE 14 - 107
FUEL SHUTDOWN SOLENOID RELAY TEST
Voltage to operate the fuel shutdown solenoid is
supplied from the ignition switch and through the
fuel shutdown solenoid relay. The fuel shutdown so­
lenoid relay is located in the engine compartment
near the brake master cylinder (Fig. 18).
To test the relay, refer to Relays—Operation/Test­
ing in this section of the group.
For removal and installation procedures, refer to
the Diesel Engine—Component Removal/Installation
section of this group.
FUEL TRANSFER PUMP PRESSURE TEST
^ For operation of the fuel transfer pump primer but­
ton, refer to Fuel Transfer Pump in the Fuel Deliv­
ery—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. 19).
FUEL TEMPERATURE SENSOR
ELECTRICAL
CONNECTOR
FUEL
HEATER
FUEL
TRANSFER
PUMP
J9414-94
Fig. 19 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 100 MM
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 pres­
sure drop across the fuel filter/water separator will
increase.. Frequent replacement of the filter may in­
dicate a worn transfer pump. The filter/separator can
be checked with a fuel pressure gauge. For test pro­
cedures, 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.
OUTPUT PRESSURE TEST
(1) Remove the clamp bolt retaining the fuel drain
manifold line to the cylinder head (Fig. 20).
J9514-68
Fig. 20 Fuel Line Fittings
(2) Remove the rear banjo fitting bolt at the inlet
line (Fig. 20).
(3) Position the fuel drain manifold line (Fig. 20) to
the rear.
(4) Install and tighten special adapter tool 6829
into the top of the fuel inlet line (Fig. 21).
(5) Install a 0-60 or 0-100 psi fuel pressure gauge
to adapter tool 6829 (Fig. 21).
(6) Start engine and record fuel pressure. Mini­
mum pressure should be 172 kPa (25 psi).
(7) If fuel pressure falls below specifications, test
for fuel line inlet restrictions before condemning the
fuel transfer pump. Proceed to step (a).