SAFETY, CARE, AND HANDLING -680640036

TM 5-2420-224-20-1

SAFETY, CARE, AND HANDLING

Warnings and cautions are listed in the front of the manual, at the beginning of each task, and

at points where they apply in the maintenance procedures. In addition to these warnings, always

keep in mind the following when working on the SEE/HMMH:

The hydraulic system operates at pressures up to 2450 psi (167 bar).

Be aware of where personnel are at all times when operating front Ioader/forklift and

backhoe/crane.

Do not allow personnel to walk under a raised front loader/forklift or backhoe/crane either

during operation or maintenance.

Always remove all jewelry and wristwatch, and make sure the vehicle MASTER disconnect

switch is OFF before working on the electrical system.

Section

Ill.

PRINCIPLES

OPERATION

OVERVIEW

This section contains information on the principles of operation of the SEE/HMMH. The general

functional description of the vehicle's separate systems is contained in this section. Unit maintenance

personnel should be familiar with the principles of operation of these systems before working on or

troubleshooting these systems. A more thorough understanding of the electrical system can be

obtained by referring to the electrical system schematic diagrams In the troubleshooting section In

Chapter 3. The systems and components are:

Page

Power Train

Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-9

Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-9

Drive Shafts . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-9

Axles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-10

Wheels and Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-10

Fuel System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-10

Exhaust System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-10

Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-11

Electrical System

Alternator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..

1-11

StarterMotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-11

Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-11

Switches and Gages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-12

Sending Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-12

Brake System

Service Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-12

Parking Brake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-12

SteeringSystem . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-13

Suspension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-13

Earthmoving, Material Handling Components and Controls

Front Loader (SEE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-14

Front Loader Controls (SEE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-14

Forklift (HMMH) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-14

Forklift Controls (HMMH) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-14

Backhoe (SEE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-15

Backhoe Controls (SEE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-15

1-8