TM 5-4320-218-15
b. With a file, make an indicating mark
inch, replace the diaphragm. If the warpage is
across the union of the fuel head (6) and the
less than 0.010 inch, flatten the flange with the
mounting bracket (18) to aid in reassembly.
use of a suitable grinder.
c. Remove the six screws (7) securing the
f. Insert the plunger (32) in the adapter and
head (6) to the bracket (18) ; remove the head.
measure the plunger-to-adapter clearance. If
the clearance exceeds 0.0045 inch, check the
d. Remove the bolt (1) and gasket (2) se-
curing the pulsator dome (3) to the fuel head;
diameter of the plunger shaft and replace the
remove the pulsator dome, valve, and filter
shaft if it measures less than 0.3712. Replace
screen (5).
the adapter if the inside diameter has worn
e. Remove the three screws (14) securing
to a dimension that exceeds 0.376.
the valve plate (13) and gasket (12) to the
g. Replace any worn gaskets, springs, or oth-
valve cover; remove the valve plate, gasket,
er damaged parts.
two valves (11), two valve springs (10), and
84. Fuel Pump Reassembly
one valve spring retainer (9). Note the posi-
tion of the valves in the fuel head.
a. Slide the rocker-arm link (19) between
the jaws of the rocket arm (21). The correct
f. Insert a suitable screwdriver into the coils
cf the rocker-arm spring (20) and pry out the
position of the rocket arm can usually be deter-
spring.
mined by matching the rocker-arm spring pro-
g. Hold the mounting bracket (18) in the
jections of both the rocker arm (21) and
left hand with the rocket arm (21) toward the
mounting bracket (18).
bracket and the thumb nail on the end of the
b. Set the large coil spring (17) (diaphragm
link (19) ; with the heel of the right hand on
spring) over the seat in the body. Place the
the diaphragm (15), compress the diaphragm
diaphragm assembly over this spring so that the
spring (17) and pull the link out from the
pull rod points down through this spring. Hold
body. This will unhook the link from the dia-
the bracket and diaphragm (16) in one hand,
phragm push rod. Remove the diaphragm and
and pinch the knob on the rocker-arm link (19)
with the thumb. This will bring the link hook
the diaphragm spring.
h. Drive out the rocker-arm pin (34), re-
up where the pull rod can reach it easily. Push
leasing the link (19) and rocker arm (21).
the diaphragm down while holding the link
i. Unscrew the priming handle (26) and re-
with the thumb. The pull rod will slip over
the link easily. Release the pressure.
move the spring (27) and shaft (29) from the
adapter (30).
c. Set the rocker-arm spring (20) in position.
j. Place the plunger (32) in a suitable vise
One end fits over the small cone cast into the
and carefully pry up on the cap (23). Make
body. The other end can be snapped over the
small projection of the rocker arm. Lay the
sure that the jaws on the vise do not damage
the plunger.
bracket on its side and insert the rocker-arm
pin (34) in the hole in the bracket (18).
83. Fuel Pump Cleaning and Inspection
d. Drop the fiber valve seat down into the
inlet-valve pocket. Then place one of the valve
a. Clean all the metal parts removed in an
springs over it. Drop the outlet-valve retainer
approved cleaning solvent. Dry thoroughly.
down into the valve hole. Then place the
b. Inspect the filter screen for tears and re-
spring over the retainer and the outlet valve on
place it if it is torn or damaged.
top of the spring. Put the retainer gasket in
c. Examine the bracket and the fuel head as-
position and place the valve retainer down on
sembly for cracks or breaks; replace if neces-
the valves so that the small holes in the retain-
sary.
er line up with the screw holes in the casting.
d. Inspect the priming handle spring for
signs of corrosion or other damage. Replace
the spring if it is bent or worn.
e. Examine the diaphragm flange for warp-
age. If the flange is warped more than 0.010
