(2)Removal.
(a) Unscrew the nut, and remove the
a. Fuel Pump.
fuel line on the-tee side of the valve (fig. 4-19).
(1) Description. The fuel pump is mounted to
(b) Unscrew and remove the valve
the fuel pump bracket which is mounted to the blower
from the pipe fitting.
housing. The fuel pump is coupled to and driven by the
electric motor operating the blower. The pump draws
(3) Inspection. Inspect the valve for worn
fuel from the fuel drum and delivers it to the burner at a
packing and for damaged threads.
maximum pressure of 100 pounds per square inch.
(4) Installation. Replace defective valve with
(2) Inspection. Inspect the pump for loose
a serviceable valve, and install it by reversing the
mounting and improper alignment. Inspect for cracked,
procedure in 1(2) above.
broken, and leaking pump.
m. Blower Motor Conduit Tube and Wires.
(3) Removal.
(1) Removal.
(a) Disconnect the fuel assemblies (8
(a) Remove the six screws that hold the
and 9, fig. 4-38) from the fuel pump (10).
cover (5, fig. 4-22) to the control panel box (4), and
remove the cover.
bolts that hold the fuel filter bracket (4) to the skid.
(b) Remove the motor wire nuts that
(c) Open the shutter, and loosen the
hold the two motor wires together, and separate the
setscrew that holds the blower shaft coupling to the fuel
wires from each other.
pump.
(c) Remove the conduit tube nut that
(d) Remove the two capscrews (6) and
holds the conduit tube to the control panel box.
the lockwasher that hold the fuel pump to the bracket.
(d) Loosen the nut that holds the
(e) Remove the fuel pump with the
conduit tube to the elbow on the motor, and slide the
filter (5) from the bracket.
tube from the water heater.
(f) Unscrew and remove the filter from
(2) Inspection. Inspect the tube for breaks,
the nipple (2).
cracks, and damaged threads. Inspect the wires for
breaks and frayed insulation. If the wires are defective,
(g) Unscrew and remove the nipple
remove the motor access plate, located at the motor
from the fuel pump (10).
end opposite the shaft end, and disconnect the wires
leading to the motor.
(h) Remove the tee (7) from the fuel
pump.
(3) Installation. Replace defective wires with
serviceable ones. Connect the wires according to the
(i) Remove the elbow (1) from the fuel
wiring diagram shown in figure 4-23, using wire nuts to
pump.
connect the motor wires at the motor, and then install
(4) Installation. Replace defective fuel pump
the motor access plate. Replace defective tube with a
with a serviceable one, and install it by reversing the
serviceable one, and install the tube by reversing the
procedure in a (3) above.
procedure in m (1) above.
(5) Adjustment. Adjust the pressure on the
n. Pressure Control Line Drain Cock.
pump to 100 pounds per square inch according to the
(1) Description. This drain cock is used to
procedures below. Adjustment must be made with the
drain the water from the pressure control line.
fuel pump operating.
(2) Removal. Unscrew and remove the drain
(a) Remove the end cap from the side
cock from the pressure control line pipe tee opposite the
of pump.
left side of the temperature and pressure control (.12,
(b) Turn the pressure regulating
setscrew as shown in figure 4-39 clockwise to increase
Inspect drain cock for dam
the pressure, and turn it counter-clockwise to decrease
(3) Inspection.
aged threads.
the pressure on the pump.
(c) Replace the end cap on the pump.
4-49
