(3) Remove two nuts (24), lockwvashers (25),
bolts (17), and spacers (21) from frame (26).
and capscrews (19) which secure right and left hand
guide plates (23 and 22) to frame (26), then remove
(5) Remove four cotter pins (29) and two pins
(30) from vertical sheave shafts (16) Drive vertical
sheave shafts (16) out and remove two sheaves (1)
from frame (26).
Do not remove bushings or bearings
unless replacement is required.
(6) Remove bearings (7) from two horizontal
(7) Remove bearings (2) from two vertical
(8) Remove six lubrication fittings (3) and
bushings (4) from two shafts (16 and 27), and two pins
(9) Reassemble by reversing steps (8)
through (1) above.
c. Cleaning, Inspection, and Repair.
(1) Clean all parts with an approved cleaning
solvent and dry thoroughly.
Figure 4-15. Clamshell bucket teeth replacement.
(2) Visually inspect all bushings and bearings
for scoring, or excessive wear; sheave shafts for
and slowly wind cables on drums, as ends are guided
excessive wear; sheaves for cracks, bends, or
excessive wear; mounting base and frame for bends,
cracks, or breaks, and mounting hardware for stripped
c. Clamshell Bucket Teeth Replacement.
threads, elongated hole, or other defects.
(3) Repair by welding cracks, or breaks;
straightening bends, or replacement of parts, repair of
(1) Removal. Position bucket on its side,
which is beyond scope or organizational maintenance.
Replace defective bearings, bushings, or mounting
six teeth from clam jaws.
(2) Cleaning, Inspection and Repair.
(a) Clean all parts with an approved
4-17. Clamshell Bucket Teeth
cleaning solvent and dry thoroughly.
a. Description. The clamshell bucket consists of
(b) Visually inspect mounting hardware
two half-scoops, hinged together at top so that they will
for stripped threads or other defects; inspect teeth for
close over material to be picked up Bucket opens when
bent, cracked, or excessively worn condition.
closing line is allowed to run free, closes when pressure
(c) Replace damaged or defective
on hoist brake is slackened and crowd and retract clutch
(3) Installation of Teeth. Install teeth on jaws
(fig. 4-15) and secure with bolts, lockwashers, and nuts.
d. Bucket Installation.
(1) Lower open bucket to ground until there is
(1) Position boom over bucket, reeve holding
slack in the holding and closing cables.
(2) Disconnect tagline from bucket and wind
sockets on bucket.
tagline on winder drum.
(2) Attach tagline to bucket.
(3) Disconnect both holding and closing