Dodge RAM TRUCK 1500 1995 Service Manual page 1097

B R
FUEL DELIVERY SYSTEM—DIESEL ENGINE 14 - 15
control direction of fuel flow and prevent fuel Meed-
back during engine shut down.
The fuel transfer pump should never be operated
without the pre-filter installed.
The fuel volume of the transfer pump will vary
with engine rpm, but will always provide more fuel
than the fuel injection pump requires. Excess fuel is
returned to the fuel tank through an overflow valve.
The valve is located on the side of the injection pump
(Fig. 7) and is used to connect the fuel return line to
the side of the injection pump. This valve opens at
approximately 152 kPa (22 psi) and returns fuel to
the fuel tank through the fuel return line.
CHECK
VALVES
A B C
LOW PRESSURE
/ SUPPLY UNE
/ RUBBER
PRIMER PUMP
BUTTON
ENGINE
CAMSHAFT
FUEL LINE
INLET
Fig. 6 Transfer Pump Operation
FUEL RETURN LINE
J9414-71
OVERFLOW
VALVE
FUEL INJECTION
PUMP
J9414-102
Fig. 7 Injection Pump Overflow Valve
MANUAL OPERATION OF TRANSFER PUMP
The transfer pump has a primer button (Fig. 8).
This rubber primer button is located on the pump
housing. The purpose of the button is to prime and
bleed air from the fuel system if the vehicle has run
out of fuel. To prime the system up to the fuel injec­
tor pump, continually press on the button (Fig. 8) un­
til resistance is felt. This resistance will indicate that
priming is completed and air has been removed.
If the primer button feels as if it is not pumping,
rotate (crank) the engine approximately 90 degrees.
This will position the engine camshaft lobe away
from the pump piston (Fig. 6). Continue pumping un­
til air is removed.
FUEL
TRANSFER
PUMP
RUBBER
PRIMER
BUTTON
J9414-72
Fig. 8 Fuel Transfer Pump—Manual Operation
For removal and installation procedures of the
transfer pump, refer to Fuel Transfer Pump in the
Diesel Engine—Component Removal/Installation sec­
tion of this group.
For diagnosis, refer to the Diesel Engine—General
Diagnosis section of this group.
FUEL FILTER/WATER SEPARATOR
The fuel filter/water separator protects the fuel in­
jection pump by removing water and contaminants
from the fuel. The separator filter construction allows
fuel to pass through it, but prevents moisture (water)
from doing so. Moisture collects at the bottom of the
separator filter.
The fuel filter/water separator is located on the left
side of the engine above the starter motor (Fig. 1).
Refer to the maintenance schedules in Group 0 in
this manual for the recommended fuel filter/water
separator replacement intervals.
For diagnosis, refer to the Diesel Engine—General
Diagnosis section of this group. -