TM 9-2330-238-14
4-61. COUNTERBALANCE MAINTENANCE (M447, M447C, AND M750) (Con’t).
3.
Inspect connecting link, link, and arm assembly for cracks, bends, or breaks. Straighten any minor bends.
4.
Inspect groove pulleys for excessive wear or cracks.
5.
Inspect counterbalance bar for cracks, bends, or breaks. Straighten any minor bends.
6.
Inspect all mounting hardware for cracks or damaged threads.
7.
Replace or repair all defective parts as necessary.
d.
ASSEMBLY
1.
Position link (18) and arm assembly (16) together with slotted holes alined. Install two new rivets (21) and
washers (17) in slotted holes.
2.
Position bracket (19) in place on end of link (18). Install headless straight pin (20) in link and lower end of wire
rope assembly (7).
3.
Aline hole in one end of connecting link (2) with middle hole in counterbalance bar (25). Install new rivet (26).
4.
Position bracket (3) in place on end of connecting link (2) and install new rivet (l).
1.
2.
3.
4.
5.
6.
7.
8.
Position two guide clip assemblies (23) and counterbalance bar (25) in place on corner post(12) and install two
screws (24).
folding side doors, and install four screws (4).
Screw turnbuckle (14) to lower end of wire rope assembly (7).
Aline holes in end of arm assembly (16) with holes in corner post (12). Position lower groove pulley (1 O) in
channel of arm assembly with wire rope assembly (7) behind upper groove pulley (1 O).
Install headed straight pin (22) in corner post (12), arm assembly (16), and lower groove pulley (10). Install
washer (8) and new cotter pin (9) on headed straight pin (22).
Position upper groove pulley (1 O) with wire rope assembly (7) behind in corner post (1 2). Install headed straight
pin (5), washer (8), and new cotter pin (9).
Aline hole in upper end of wire rope assembly (7) with top hole in counterbalance bar (25). Install headed
straight pin (6) and new cotter pin (11).
Remove jacks or blocking from lower folding side door.
f..
ADJUSTMENT I
1.
Loosen nuts (13 and 15).
2.
Turn turnbuckle(14) clockwise or counterclockwise until proper tension is obtained on wire rope assembly(7).
Tighten nuts (13 and 15) on each end of wire rope assembly to lock turnbuckle in position.
3.
Lubricate turnbuckle (14) and groove pulleys (1 O) in accordance with Lubrication Instructions (Chapter 3,
Section l).
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