CRANE - BOOM EMERGENCY LOWERING SWITCH

TM 5-5420-279-23

CRANE - BOOM EMERGENCY LOWERING SWITCH

This task covers:

a. Remove

b. Service

c. Install

INITIAL SETUP:

Tools Required

Tool Kit, General Mechanic's, Automotive (GMTK)

Materials Required

Thread locking compound, loctite 243

Hydraulic fluid

Equipment Conditions

Crane in the stowed position

WARNING

INJURY FROM EXTREME HYDRAULIC OIL PRESSURE. THE SYSTEM MUST BE

DE-PRESSURIZED BEFORE CARRYING OUT ANY WORK ON THE BOOM

EMERGENCY LOWERING SWITCH.

INJURY FROM EXTREME HYDRAULIC OIL PRESSURE. THE CRANE MUST BE IN

THE STOWED POSITION BEFORE REMOVING ANY OF THE HYDRAULIC PIPES

CONNECTED TO THE BOOM EMERGENCY LOWERING SWITCH.

SLIP AND FALL INJURY. PERSONNEL MAY SLIP ON SPILLED HYDRAULIC

FLUID. SUITABLE CONTAINERS AND FLUID ABSORBENT MATERIALS ARE TO

BE USED TO CONTAIN SPILLAGE.

NOTE

The Boom emergency lowering switch is located on the lifting cylinder. If the lift cylinder

is fully extended and the overload protection device switches off crane operations, the

boom can be enabled by operating the boom emergency lowering switch. See operator's

manual TM 5-5420-279-10.

6-174 Change 1