cleaning, wipe housing dry. Dip flingers and adjacent parts in SAE 10 mineral oil, heated to 203F., and
drain. Store parts in a dry, clean place.
On any shaft having two bearings, one is suitable for taking end thrust and is clamped
rigidly to take this thrust; the other must be free to allow end movement which results from expansion or
contraction of the shaft when temperature changes.
2.30. SEQUENCE TESTING
Electrical testing instructions are issued by the manufacturer for each group of locomotives.
These tests must be followed accurately, with no attempt to adopt substitutions. The following
discussion of typical testing procedures merely tells what is usually done and why it is done. The
operating sequence of shutdown control circuits can be tested at battery voltage by manually moving
interlocks and controls. Disconnect the generator first, however, so that it will not crank the engine or
produce power voltage. When testing, keep the following things in mind:
Starting circuit interlocks must prevent the armature contactors from closing until the field
contactors have closed.
The fuel pump must operate so that proper pressure shows on the fuel gage. The shutdown valve
in fuel line must function with any safety devices, such as low oil pressure switch or high water
temperature switch, according to the wiring in each individual case.
Interlocks between the throttle and reverser and those in fan motor circuits and shutter control
circuits must function properly.
Any auxiliary equipment, such as sanders, must operate.
Traction motor field shunting and transition must occur at the proper time and sequence.
Wheel slip relays, ground relays, etc., must give proper protection and turn on the alarm and
Any replaced traction motor must be checked for proper direction of rotation and direction of