and thermocouples, voltmeter and ammeter with shunts and pressure gages; and thermometers and
temperature indicators--a part of the regular engine equipment.
Various maintenance services are ordinarily performed during routine maintenance inspections.
Cleaning and lubrication are the major part of maintenance. Small inexpensive parts may be easier to
replace than to repair and such replacements are often ordered. Other parts, such as fuses and some
filters, are necessarily replaced. Balancing and adjustment of parts are also common.
Remove and inspect cast aluminum bearings every 75,000 miles and forged aluminum ones
every 85,000 miles. Remove and check bearings, being careful to avoid scratching them or distorting
their shells. Clean and lubricate trucks periodically and turn, renew, or replace wheels and axles.
Periodically pack journal boxes and bearings, adjust brakes or replace brake parts, and check the fuel
system. Oil the moving parts of the cooling system and replenish it with treated water. Whatever the
maintenance job, be sure to comply with manufacturer's instructions and standard shop procedures.
Section II. Electrical Maintenance and Repair
Maintenance of electrical equipment involves cleaning, lubricating, adjusting, and occasionally
replacing parts. Cleaning is done by blowing dust out of the equipment with compressed air. If the air
is not sufficient, equipment can be brushed with a dry cloth or one dampened with a solvent. Parts are
lubricated according to standard lubrication orders; adjustments and replacements are made when
The accepted procedures for maintaining specific pieces of electrical equipment are given in this
section. Generators and motors are discussed first, then main power switches, voltage and load
regulators, reversers, battery, bearings, and sequence and insulation testing. Although the coil and the
commutator are parts of a generator or a motor, they are discussed separately for clarity.