CAPSTAN, REELS, AND BLOWER

Procedures for replacing the capstan motor, file reel hub, file and machine reel motors, and vacuum blower are given in the following sections.

8.4.1 Capstan Motor Replacement

1. Switch off the main circuit breaker.

2. Disconnect J14 from the file reel motor, Ji7 from the retractor motor, J18 from the vacuum blower motor, and J23 from the upper swing arm tach.

3. Disconnect J16 from the capstan motor.

4. Remove the four screws that secure the vacuum blower adapter to the deck casting. Remove the blower and adapter assembly.

5. Remove the seal from around the capstan motor. Remove all the screws that secure the vacuum plenum cover to the deck casting. Remove the plenum cover.

6. At the front of the deck casting, remove the screw that secures the capstan wheel to the motor shaft. Remove the caps tan whee 1 .

7. Each of the three capstan motor mounting screws retains a spring between the capstan motor and the deck casting. These springs are required during reassembly and are critical to proper operation.

Equally loosen the three screws that secure the capstan motor to the deck casting while supporting the capstan motor from the rear, but do not pull the screws from the casting until you can remove the springs from the rear. Remove the springs and store them safely for reassembly.

8. Reassemble all components in reverse order of disassembly.

Position the capstan motor with the tach cable to the left (as viewed from the rear) and route the cable through the groove in the casting directly below the motor.

Insert the three capstan motor mounting screws front of the casting and slide the springs on threaded portions of the screws from the rear.

through the the exposed 9. With the springs properly placed on the screws, install the motor and moderately tighten the screws. Tighten screws alternately and equally to prevent stripping.

10. Back off each mounting screw by one complete turn.

11. Clean and replace the plenum cover. Ensure that all cables emerging from the vacuum plenum are located properly in their respective slots in the deck casting before tightening the plenum cover retaining screws. Replace the seal around the capstan motor, ensuring that the wide flange is pressed against the plenum cover.

12. Reinstall the vacuum blower and adapter assembly.

13. Reconnect 014 to the file reel motor, 016 to the capstan motor, J17 to the retractor motor, J18 to the vacuum blower motor, and J23 to the upper swing arm tach.

14. Perform the tape tracking and skew procedure (refer to

8.4.3 File Reel Motor Replacement

1, Switch off the main circuit breaker.

4. Remove the three screws that secure the hub assembly to the clamp collar and remove the hub assembly.

5. Remove wire tie from rear of motor

6, Remove the four screws that secure the reel motor to the deck casting and remove the motor.

7. Reassemble in reverse order. The outer edge of the clamp collar should be positioned 0.816 in. ±0.002 in. (2.07 ±0.005 cm) from the front of the reel motor.

8. To check for proper alignment of the reel to the tape path, power up the MTS, mount and load a scratch tape, enter maintenance program 00, and run tape forward to EDT. ' Rewind while observing the tape as it wraps back on the file reel:

the tape should not contact either flange of the reel. If necessary, use the clamp collar to reposition the hub until the tape wraps on the reel without contacting the reel flanges.

9. Check the alignment and operation of the file protect sensor.

To check for proper operation of file protect, load a scratch tape with a write enable ring installed and check that the file protect indicator turns off. Unload the tape, remove the ring, reload the tape, and check that the file protect indicator ;s illuminated.

8.4.4 Machine Reel Motor Replacement 1. Switch off the main circuit breaker.

2. Disconnect J15 from the reel motor.

3. Remove the machine reel cover.

4. Remove the three screws that secure the machine reel hub cap to the hub and remove the cap and outer flange,

5, Remove the three screws that secure the hub assembly to the clamp collar and remove the hub assembly.

6. From the front of the deck casting, that secure the machine reel motor Remove the motor.

remove the four screws to the deck casting.

7. Install the replacement reel motor. The outer edge of the clamp collar should be positioned 0.642 ±0.005 in. (1.63

±0.013 cm) from the front of the reel motor.

8. Reassemble all components in reverse order. Ensure that the rim of the outer flange is positioned outwards.

9. Power up the MTS and load a scratch tape. Enter maintenance program 00 to run the tape forward. Check for proper alignment of the reel to the tape path. The tape should not contact either flange of the reel as it wraps on the machine reel, You may remove the column door and the machine reel cover once the tape has been loaded to observe the machine reel area.

If necessary, use the clamp collar to reposition the hub on the motor shaft until the tape wraps on the reel without contacting the reel flanges.

8.4.5 Vacuum Blower Replacement

1. Switch off the main circuit breaker.

2. Disconnect J18 from the vacuum blower.

3. Remove the four screws that secure the vacuum blower to the vacuum blower adapter. Remove the blower.

4. Remove the blower mounting plate from the blower and install the plate on the replacement blower.

5, Reassemble in reverse order. When installing the four screws, make sure that the threads of all the screws are caught before completely tightening anyone screw. Reconnect J18 and check the subsystem by performing at least 10 tape load operations.