TM 9-2320-280-34
14-13. AMBULANCE HEATER FUEL CONTROL VALVE TESTING AND ADJUSTMENT
(MODEL 10530B) (Cont'd)
2.
Make sure power source is disconnected. Turn two dzus fasteners (2) and remove guard (1) from
control bracket (3)
3.
Loosen nut (4) and disconnect fuel tube (5) from control valve outlet (7).
4.
Connect one end of nonmetallic tubing (6) on control valve outlet (7) and place other end in
graduated beaker or similar container.
5.
Disconnect lead 3 (16) from shunt resistor (17) to disable the motor and igniter.
6.
Disconnect lead 15 (12) from fuel valve (14) to disable fuel valve (14).
7.
Connect power source and place HI-LO switch to LO position.
NOTE
Have drainage container ready to catch fuel.
8.
Open bleed valve (15) on fuel valve (14) to remove air from fuel flow. Close bleed valve (14) when
fuel flow is free of air bubbles.
9.
Connect lead 15 (12) to fuel valve (14).
10.
Disconnect lead 17 (11) from fuel valve (14).
11.
Partially raise lead (12) and place switch in start position.
12.
Connect jumper lead (13) to lead 17 (11) terminal and lead 15 (12) terminal. A clicking sound
should increase in rate.
13.
Connect 50 in. (127 cm) long, and .187 in. (4.7 mm) diameter clear nonmetallic tubing to bleed
valve (15) and position the open end of nonmetallic tube (18) at least 45 in. (114 cm) higher than bleed
valve. Open bleed valve (15) and allow fuel to flow up the nonmetallic tube (18) until it stabilizes.
14.
From bleed valve (15) measure vertically the height of fuel. Fuel should be between 36 to 40 in. (91
to 102 cm) from bleed valve (15). If adjustment is necessary, proceed to step 15. If not, proceed to
step 16.
15.
Adjust height (regulated pressure) by turning the regulated pressure adjustment screw (10). If
height will not adjust or stabilize, then replace valve (para. 14-11). Close bleed valve (15).
16.
Disconnect nonmetallic tube (18) from bleed valve (15). Turn fuel pump off.
17.
Disconnect jumper lead (13) from terminals (11) and (12).
NOTE
Low fuel flow rate must be set before high fuel flow can be set.
18.
Operate fuel pump for one minute and stop.
19.
Repeat step 13.
20.
Disconnect jumper lead (13) from terminals (11) and (12).
21.
Record amount of fuel accumulated in graduated beaker. The fuel flow rate must be 0 to 10cc per
minute.
22.
If flow rate is not within limits, turn adjusting screw (9) clockwise to lower flow rate or
counterclockwise to raise flow rate. If flow rate is not obtainable, replace fuel valve (para. 14-11).
23.
Place HI-LO switch in HI position.
24.
Operate fuel pump for one minute and stop.
25.
Repeat step 13.
26.
Disconnect jumper lead (13) from terminals (11) and (12).
27.
Record amount of fuel accumulated in graduated beaker. High fuel flow rate should be 20 cc per
minute.
28.
If flow rate is not within limits, turn adjusting screw (8) clockwise to lower flow rate or counter-
clockwise to raise flow rate. If flow rate is not obtainable, replace fuel valve (para. 14-11).
29.
Apply insulating varnish to adjusting screws (8), (9), and (10).
30.
Connect lead 17 (12) to fuel valve (14).
31.
Connect lead 3 (16) to shunt resistor (17).
32.
Remove fuel tubing (6) from control valve outlet (7).
14-78
Change 2
