Section IV. CORRECTIVE MAINTENANCE

TM 9-6685-202-14 , C1

Table 4-3. Trouble Shooting Chart-Continued

Trouble

Probable Cause

Remedy

Applied correction

Cam bar bent more

Return to depot

scale errors large

than 0.001 inch.

maintenance shop

at midrange.

for repair.

Instrument does not

Improperly leveled

Level instrument

read 0.1 mm (0.004

(para 3-5).

inch) with tube and

cistern at same

Incorrect amount of

Check mercury level

pressure.

mercury.

(para 4-5a).

Instrument can be

Improperly leveled

Level instrument

pulled below zero

(para 3-5).

with vacuum on

cistern and tube

evacuated.

Incorrect amount of

Check mercury level

mercury in cistern.

(para 4-5a).

Improperly evacuated

Reevacuate tube

tube.

(para 3-5).

Section IV. CORRECTIVE MAINTENANCE

10.

Tube, barometer (includes valve

4-11. General

subassembly) HIC 10-00-15-C

This section includes instructions for the disassembly

11. Screw, cap, socket head HIC 10-32 x 3/4

and assembly of the type A-1 and the type A-1 modified

12. Block HIC 10-30-16-B

barometer, vacuum pumps 4310-203-3057 and 4931-

13. Setscrew HIC 4-40 x 1/8

929-8403, and constant vacuum regulator 6685-306-

14. Screw, cap, socket head, HIC 4-40 x 1/2

5604 as far as necessary to replace spare parts

15. Washer, flat HIC No. 4

authorized in appendix C. The exploded views in this

16. Clamp, cable HIC 1/8 in. dia

section show the sequence of disassembly. The parts

17. Screw, cap, socket headHIC4-40 x 3/8

illustrated are keyed by number callouts to a table of

18. Jack, tip, light source HIC 12-A-1055

established nomenclature accompanying each figure.

19. Vernier slide assembly

4-12. Disassembly

20. Holder, thermometer HIC 10-41-03-A

KEY to fig. 4-3

21. Screw, cap, socket head HIC 4-40 x 3/8

1. Evacuation manifold

22. Thermometer HIC 10-41-01-A

2. Screw, machine MS-35207-261

23. Insert, clay block (commercial)

3. Clamp, loop, plastic MS-25281-F6

24. Bar, cam HIC 10-30-01-C

4. Union, reducing 7913085

25. Stud, cam bar HIC 10-30-02-B

5. Sleeve, top cap HIC 10-00-13

26. Screw, cap, socket head HIC 4-40x3/4

6. Screw, cap, socket head HIC 6-32 x 1/4

27. Washer, flat HIC No. 4

7. Tubing, plastic HIC 3/16 OD 1/16 ID x 1 1/4

28. Washer, flat HIC 10-30-30

29. Scale, HIC 10-30-19-B (7913097-1)

8. Nipple, tube evacuating HIC 10-00-11A

30. Screw, cap, socket head HIC 4-40x 3/l8

9. Disc, top mounting HIC 10-00-14-C

4-10