TM-9-2320-272-10

TRUCK, 5-TON, 6X6, M939, M939A1, AND M939A2 SERIES TRUCKS (DIESEL)

TECHNICAL MANUAL; OPERATOR'S MANUAL

SEPTEMBER 2004

CHANGE 2

TM-9-2320-272-10 - Page 238 of 481

TM 9-2320-272-10

2-24. OPERATION OF MEDIUM WRECKER (Contd)

2-137

(12)

To lift and swing load:

NOTE

This operation requires use of all outriggers.

(a)

Perform steps 1 through 9.

(b)

Slightly pull boom control lever (6) back to UP to take boom (1)

weight off shipper braces (12).

(c)

Remove retaining clips (16)

from L-shaped shipper brace retaining

pins (14) and remove pins (14) from shipper

brace brackets (13).

(d)

Swing brace (12) upward to

brace retaining brackets (10) on each side of

shipper (11). Secure braces (12) on

brackets (10) with retaining clips (15).

CAUTION

When extending boom, move HOIST

and CROWD levers at the same time.

Failure to do so may result in boom

damage.

(e)

Extend boom (1) as necessary

by pushing crowd control lever (8) forward to

DOWN. Maintain an even distance between

crane block (3) and boom sheaves (2).

(f)

Elevate boom (1) to desired

height by pulling boom control lever (6) back

to UP.

(g)

Lift load (5). Refer to step 10.

CAUTION

Boom rotates 360°. Make sure area is

clear of obstacles, and caution is used

when operating boom over cab area.

Damage to windshield, exhaust stack,

air intake, and cab may result.

(h)

Push swing control lever (9) forward to LEFT to swing load (5) left.

Pull swing control lever (9) back to RIGHT to swing load (5) right.

(i)

Lower load. Refer to step 11.