TM-5-2330-378-14-P

SEMITRAILER, LOWBED: 40 TON CONSTRUCTION EQUIPMENT TRANSPORTER M870 AND M870A1

TECHNICAL MANUAL; OPERATOR'S, UNIT, DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE MANUAL (INCLUDING REPAIR PARTS AND SPECIAL TOOLS LIST)

JUNE 1999

TM-5-2330-378-14-P - Page 209 of 524

TM 5-2330-378-14&P

4-55. MULTIFUNCTION

VALVE

REPLACEMENT

AND

OPERATING

TEST

(M870)

(continued).

lb.

INSTALLATION

1.

Install multifunction

valve

(2), new

lockwasher(3),

and cross

tube

fitting

(4) on mounting

bracket

(5).

2.

Connect 11 air lines (1) to multifunction valve (2). Check tagged air lines with schematic (Appendix J).

3.

Close drain cocks (para 3-8).

C.

OPERATING

TEST

WARNING

Wear

protective

goggles

when

opening

air reservoir

drain

cocks.

Avoid

contactwith

the air stream.

I

Pressurize semitrailer air system (para 3-8). Shut off towing vehicle engine. The tires on the front and middle

axles of semitrailer should lock. Open drain cock on front air reservoir.

2.

After air system is bled down, tires on front and middle axles should remain locked. Coat front reservoir drain

cock with a solution of detergent (item 4, Appendix F) and water.

3.

Leakage at open front reservoirdrain cock should notexceed aone-inch (2.5 cm) bubble infive seconds. Ifexcess

leakage isfound, replace multifunction valve (subparas 4-55a and4-55b).

4.

Close front reservoir drain cock.

5.

Repeat steps 1 through 4 for drain cock on middle air reservoir.

FOLLOW-ON TASKS:

• Check airbrake system for leaks (Table 2-1, item numbers 11 and 13).

• Check operation of brakes (subpara 4-54c).

• Stow planks (para 2-10).

4-121