Perform the following procedure to install the lead tower on the crane boom nose:
Ensure the Load Moment Indicator (LMI) system on the crane is configured for
Rear Hoist, Outrigger Position 100%, and Two (2) Parts of Line.
Reposition the wire rope lifting sling and nylon lifting sling to the top of the lead
tower. Use the pile line (aux. hoist) of the crane to lift the top of the lead tower and
allow the base to roll out until the lead head adapter is approximately 37-38 feet
(11.3-11.6 m) from the rear of the crane and inline with the boom assembly.
Lower the lead tower onto wooden blocks placed near the lead head adapter at the
top of the lead tower. The blocks should be sufficient to raise the top of the lead
tower approximately 30-inches (76 cm) high.
With the crane's boom aligned with the lead tower, lower the boom to its lower
limit. The boom should be at a negative angle.
Raise the rear outriggers until the rear wheels are touching the ground. Then
lower the front outriggers to tilt the crane towards the rear.
Remove the bolts and washer securing the locking collars to the two lower boom
nose shafts and remove the locking collars from the shafts.
The lead head adapter attaches to the crane boom nose via two
boom nose adapters plates, one on each side. These plates are
located in the crane's tool box. The left and right side adapter
plates are different and are stenciled with the words LEFT and
RIGHT. Each must be installed on the correct side of the boom
nose with the bushing installed inward toward the boom nose.
Install the boom nose adapter plates, locking collars, nuts, and lockwashers with
the boss portion of the boom nose adapter plates facing inwards. Ensure that all
hardware is secure and that the boom nose adapter plates swing freely.
Remove and retain the nuts, bolts, and lockwashers installed in the lead head
Telescope the boom out approximately 50 feet (15 m). Be sure to pay out the
hammer line (main hoist) and pile line (aux. hoist) cables while extending the
boom. Telescope slowly as the boom tip approaches the lead head adapter
brackets. Align the hammer line (main hoist) and pile line (aux. hoist) cables along
one side of the lead tower.
This procedure presents several opportunities for pinching body
parts. Use care when lining up the boom nose adapter plates with
the lead head adapter.
Rotate the boom nose adapter plates to horizontal and telescope and raise or
lower the boom until the bolt hole patterns on the adapter plates line up with holes
in the lead head adapter bracket. Use the tapered end of a pry bar to line up the
bolt hole patterns.
Change 1 H-43