OP-755 Part 2 Pages 197-401 - Personal Page of GENE SLOVER

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started. The starting handle is to be held in the Ilstartll
position, and the car isto be hoisted slowly until it contacts
the upper buffer. The car will b~ stopped by the buffer, but
the starting valve held in the start position prevents venting
the main circuit lines. The pressure reading shown on
the gauge indicates the setting of the relief valve. The relief
valve is to be adjusted to crack at 2100 P.S. I., by removing
cap 274311-2, loosening lock nut 2743:J.9- 3, and screwing
Ilin" or Iloutll on the adjusting screw 274324-5. Screwing
"in" onvth e adjusting screw will increase the pressure. An
approximately correct setting of the relief valve will be obtained
by screwing in the adjusting screw as far as possible,
and then "back-outll 1-1/2 turns.
85. Brake adjus tmen ts. - Refer drawing number 274249.
The brake is adjustable to provide for wear, at the brake band
end 274318-3, and at the four eccentric stop pins 274307-2,
and -t.he two adjusting stop screws 274J28~10. ;A maximumdimension
of three inches', and a minimumdimension of 2-3/4 inches
locating the end of the brake cylinder piston 2'74318-1 from
the face of ,the .cylinder cap 274317-2 is shownon the drawing.
The brake is to be adjusted to the three inch dimension, this
will provide 1/4, inch of piston travel to provide for wear before
it becomes necessary to readjust the brake.
CAUTION:.The distance from the end of the brake cylinder piston
to the cylinder cap should never be allowed to become less
th~n 2-3/4 inches. This should be checked at frequent interval§.
",'
With the hoist in the "Stopped" position (brake applied) and
the controls set for a "Servo Controlled" cycle, the two lock
nuts 274339-4 are to be loosened, and the upper adjusting nut
206522-3 is to be backed off. Tighten the lower adjusting nut
206522-3 until the three inch dimensio'ri. is obtained.
Nowplace the starting handle in the "Start!1 position, which
releases the brake, and check with a '.010 inch feeler gauge
to see if there is clearance all around the band. This clearance
can be maintained by adjusting the stop screws 274328-10
which are located on the top of the brake cylinder, and also
by the eccentric stop pins 274307-2. Remove the cotter pins
274341-3, and loosen slightly the slotted nuts 274339-5. Use
a wrench on the flats,provided on the ends of the stop pins,
and turn the pins until clearance is obtained all around the
brake band. After clearance has been obtained, hold the stop
pins with a wrench, and secure the slotted nuts 274339-5. Replace
the cotter pins.
86. To adjust the foot valve control linkage. - With
the' A-endheld in its center position by the centering plungers,