TM 9-4910-663-34
(2)
Remove the five sheet metal screws that attach the blower assembly inlet flange, and remove the inlet
flange.
(3)
Loosen the setscrew in the blower wheel, and remove the blower wheel.
(4)
Remove the four 10-32 nuts that secure the blower housing and back plate to the blower motor, and
remove the blower housing.
(5)
Remove the rubber washers, flat washers, and spacers.
(6)
Reverse the procedures of steps (1) through (5) to install the replacement blower motor.
Section II. GENERAL SUPPORT REPAIR INSTRUCTIONS
3-18. PC BOARD ASSEMBLY
a.
General. Repair of the PC board assembly is done by locating the defective part through resistance checks, and
removing and replacing that part. See figure 3-3 for parts identification. The PC board assembly must be removed from
the test stand for repair. Refer to para 2-13 for removal.
b.
Testing of PC Board Assembly.
(1)
Using an ohmmeter, measure the resistance of resistor R33 between terminals 1 and 2 of the PC board
assembly. The resistance should be 2740 ohms ±1%.
(2)
Connect the ohmmeter between terminal 2 of the PC board assembly and the center terminal of
potentiometer R36. The resistance should be 15,000 ohms ±1%. Replace resistor R34 if the correct reading is not
obtained.
(3)
Connect the ohmmeter between terminal 7 of the PC board assembly and the center terminal of
potentiometer R36. The resistance should be variable from zero to 10,000 ohms ±10% by adjusting potentiometer R36.
Replace the potentiometer if the correct indication is not obtained.
(4)
Connect the ohmmeter between terminals 3 and 4 of the PC board assembly. The resistance should be
24,900 ohms ±1%. Replace resistor R25 if the correct indication is not obtained.
(5)
Connect the ohmmeter between terminal 5 of the PC board assembly and the center terminal of
potentiometer R20. The resistance should be 750 ohms ±1%. Replace resistor R22 if the correct indication is not
obtained.
3-31
