15-45. CEILING AIR DUCTS AND SUPPORTS REPLACEMENT (Cont'd)
b. Installation
NOTE
Insulate areas of dissimilar metal-to-metal contact with zinc
chromate primer.
1.
Install support (2) on ceiling (3) with eleven screws (4).
2. Install support (5) on ceiling (3) with ten screws (6).
3. Install air duct (1) on ceiling (3) with sixteen screws (7).
4. Install air, duct (9) on ceiling (3) with eighteen screws (7).
5. Secure air ducts (1) and (9) to supports (2) and (5) with four screws (10) and eight screws (8).
NOTE
Perform step 6 for M820 and M820A2 vehicles.
Perform step 7 for M820A1 vehicles.
6. Install two enclosures (11) on air ducts (1) and (9) with fifty-two screws (12).
7. Install two enclosures (11) on air ducts (1) and (9) with seventy-two screws (12).
8. Install support (14) on ceiling (3) with nine screws (13).
9. Install air duct (18) on ceiling (3) with eighteen screws (21).
10. Install air duct (15) on ceiling (3) with sixteen screws (16).
11. Secure air ducts (18) and (15) to support ( 14) with fourteen screws ( 17).
NOTE
Perform step 12 for M820 and M820A2 vehicles.
Perform step 13 for M820A1 vehicles.
12. Install two enclosures (20) on air ducts (15) and (18) with fifty-two screws (19)
13. Install two enclosures (20) on air ducts (15) and ( 18) with seventy-two screws (19).
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