Figure 3-39. Propel chain adjustment.
(1)Panel lights.
Remove cover by turning
bolts are drawn up tight to adjusting blocks to
counterclockwise; remove defective lamp by pressing in
secure the adjustment.
and turning counterclockwise to free prongs. Insert new
(2)Measure compressed length of springs. Each
lamp and install cover by reversing this procedure.
spring should measure 31 inches. To adjust length,
(2)Cab lights. Remove lamp by pressing in and
backoff, or tighten spring adjusting nut (fig. 3-40), until
turning counterclockwise to free prongs. Insert new
length is correct.
lamp, push in, and turn clockwise to engage prongs of
Caution:
Correct tension on springs is
lamp in socket of holder.
necessary to take up shock when small stones
lodge between idler sprocket and crawler shoes.
3-43. Cable Replacement
a. Cable Removal. To replace a defective cable,
3-42. Instrument Panel and Cab Light Lamp
from shovel hoist drum or when changing front end
Replacement
attachment, proceed as follows.
a. General.
Illumination for performance of
(1)Remove cable clamps securing cable in dead
preventive maintenance checks and services on
end socket on right hand boom point sheave (fig. 2-19).
operating machinery within cab enclosure is furnished
(2)Slowly wind cable on drum through right hand
by lamps in holders on cab ceiling behind operators seat
boom point sheave, dipper sheave, and left hand boom
and on left rear side. These lamps are to be augmented
point sheave.
by use of trouble light (para 2-27).
Panel lights
(3)Unwind cable from hoist drum, carefully coiling
illuminate instruments on control stand and switches on
slack in a suitable box, or on a reel, then disconnect
lighting control panel.
b. Lamp Replacement.
3-45
