Mast Repair
REMOVE
WARNING
The mast and carriage assemblies, and their com-
ponents, are heavy. To help prevent damage or an
injury, a lifting device must be used during all
service procedures. The mast weighs approxi-
mately 318 kg (700 lb).
1.
Block the mast in the service position. See the
Operating Manual or the Periodic Mainte-
nance manual listed in the General section of
this manual for procedures to block the mast.
2.
Remove nut, spring, and washer from first
phasing cable. See Figure 5.
3.
Remove first phasing cable from bracket on sec-
ond intermediate mast weldment. See Figure 5.
4.
Using lower control panel, lift aerial work plat-
form and remove the pipe. Return mast to fully
lowered position.
5.
Remove dust covers from top of mast channels.
See Figure 6.
WARNING
Be careful when removing or installing snap
rings. These snap rings can come loose during re-
moval or installation with enough force to cause
an injury. Always use the correct snap ring pliers,
and wear eye and face protection during removal
or installation.
6.
Remove snap ring from lift cylinder. See Fig-
ure 6.
WARNING
The mast and carriage assemblies, and their com-
ponents, are heavy. To help prevent damage or an
injury, use a lifting device with a minimum ca-
pacity of 318 kg (700 lb).
7.
Place a sling strap under the top cross bars of
all five mast channels. See Figure 6.
8.
Turn off all power to aerial work platform by
disconnecting the battery and discharging the
capacitors. See the Special Precautions section
for procedures to discharge the capacitors.
9.
Zip tie lift cylinder to frame before removing
mast from aerial work platform.
10.
Remove operator compartment. See Operator
Compartment manual listed in the General
section of this manual for procedures.
11.
Open service doors for access to electrical con-
nections and components.
12.
Remove mast cable tensioning system by un-
hooking spring and pulling spring and wire
harness cable off of round belt pulley. Set mast
cable tensioning system off to side. See Fig-
ure 7.
NOTE:
Be sure to tag all electrical connections
prior to disconnecting them to help in reconnecting
them during installation.
13.
Disconnect mast signal cable from lower control
panel. See Figure 7.
CAUTION
Frame slider blocks do not need to be removed
from mast frame after removing threaded screws.
When mast is raised with lifting device during re-
moval from aerial work platform frame, slider
blocks will come off. Be sure slider blocks do
come off when removing mast from frame. If they
do not fall off, the mast will pull slider blocks out
of frame and cause damage to mast and slider
blocks.
14.
Remove threaded screws from frame slider
blocks. See Figure 6.
15.
Raise mast 102 to 152 mm (4 to 6 in.) with lift-
ing device attached to sling strap. This will pro-
vide slack to first set of lift chains that connect
frame to second intermediate mast weldment
channel.
Mast Repair
4000 SRM 1916
6