case.
(10) Refill gear case per lubrication order.
4-4.
Revolving Frame
a. General. The revolving frame is a one-piece,
heat treated steel casting with integral lugs for boom foot
and cone roller mounting brackets. Cast steel machinery
side frames are bolted to revolving frame. Shear plugs
relieve bolts of shear loads and maintain alignment.
b. Inspection and Repair. Clean up frame and
inspect for cracks, broken welds and other defects. Make
repair by welding and grinding. For bushing inspection and
repair procedure, see paragraph 2-5.
4-5.
Chain Case Assembly
a. Removal
(1) Swing revolving frame cross-wise of the
tread belts so the case can be taken out between the
crawler side frame.
(2) Remove chain case cover (20, fig. 4-1)
and gasket.
Figure 4-7. Vertical swing shaft repair and replacement.
(3) Drain chain case by removing plug (27).
(9) Remove cotter pin and nut at upper end of
(4) Remove level gage plug on right side
shaft and tap down lightly with babbitt hammer just enough
under revolving frame.
to force through upper bearing.
(5) Remove nuts, screws and washers from
(10) Pinion drops with the shaft and may be
forward and rear support brackets; remove rear support
removed from shaft by taking out the two capscrews, lock
bracket and drop case into hole in revolving frame.
plate, and removing the retainer plate.
(6) Slide case to rear and drop out through
(11) The upper bearing can be lifted out. The
revolving frame.
lower bearing can be tapped off from the shaft if necessary.
Note. Side member of revolving frame to left of
Note. If repair involves only the replacement of
case is removable if desired by removing three bolt at
the pinion this an easily be removed without any of the
rear, two bolts t front and four bolts that come up
above steps except paragraph 20.
through sill.
(12) Jaw clutch and combination bevel gear
b. Installation
can be tilted and lifted out, after removing steering and
(1) Installation is the reverse of removal
digging lock horizontal shafts.
procedure, a above.
(13) There are still two ball bearings mounted
(2) Refer to the lubrication order and service
in the combination gear. If it is necessary to remove these,
the chain case assembly.
tap down from bevel pinion end. The spacer between
4-6.
Vertical Swing Shaft (fig. 4-4 and 4-7)
bearings will come out with bearings.
a. Disassembly.
b.
Inspection and Repair.
Clean all parts
(1) Swing machine so that shaft can be
thoroughly and inspect for damage and excessive wear.
dropped down clear of the truck frame.
For gear and bearing inspection and repair, see
(2) Remove swing and propel gear case
paragraph 2-8. Replace defective gaskets and hardware.
cover (fig. 4-2).
Rebuild broken or worn jaw clutch splines or jaws by
(3) Drain oil from sump of main gear case
welding and grinding. Replace worn or damaged oil
through two drain plugs (fig. 4-3).
retainer.
(4) Loosen bolt at split hub of swing jaw
c. Reassembly.
clutch shifter and at the hand lever and pull hand lever shaft
(1) Replace top bearing, spacer, and lower
out taking care not to lose key.
bearing in combination gear if they have been removed.
(5) Remove propel jaw clutch shifter shoe
Place shield on upper side of top bearing.
pins and shoes.
(2) If oil seal at bottom of case is damaged,
(6) Take out clutch shifter.
replace in revolving frame.
(7) Remove vertical shaft cover and gasket
(3) Assemble pinion gearing with shield
by taking out four capscrews.
towards pinion, and pinion on lower end of shaft securing in
(8) Prepare blocking and extended jack under
place with retainer, two capscrews and lock plate.
vertical swing shaft to provide for lowering it safely (pinion
(4) Place combination gear and jaw clutch in
weight 50 pounds and shaft 80 pounds).
place in case and insert shaft from below.
4-9
