4000 SRM 482
Mast Adjustments
The only adjustment for the load rollers is the ad-
justment of the wear plugs. These adjustments are
made for minimum side clearance and to keep the
weldments parallel with equal clearance on each side
between all weldments.
Wear plugs and wear strips allow adjustment for
alignment and wear. Always adjust the wear plugs
and wear strips for one weldment before making
adjustments on other weldments.
Chains are adjusted for the following reasons:
• So each lift chain of a pair has an equal load to
prevent too much load and wear on one chain of
a pair.
• So mast weldments move in the correct sequence.
• So chains move over chain sheaves correctly.
Adjustments must be made to both the free-lift
(three-stage only) and main-lift chain sets. Each lift
chain is adjusted at the chain anchor.
ADJUST WEAR PLUGS - MAST
Adjust the wear plugs as follows:
1.
Loosen the jam nut on the wear plug. See Fig-
ure 24 and Figure 25. Raise and lower the mast
weldments several times to find the point of min-
imum clearance of the weldment.
2.
Adjust the wear plugs to attain zero clearance be-
tween the wear plug and the weldment channel
at the tightest point. Adjust wear plugs on oppo-
site sides to keep the weldment in the center.
3.
Adjust the clearance to approximately 0.02 in. by
turning the adjustment handle 1/8 turn counter-
clockwise. Keep the clearance between the weld-
ments equal on both sides. Keep the weldments
parallel to each other.
4.
Tighten each jam nut without moving the
setscrew.
5.
Raise and lower the weldments without a load.
Check that there is minimum clearance, as de-
scribed in Step 3, with free movement. If the
weldments do not move smoothly during lower-
ing, follow the WARNING and adjust the wear
plugs equally for more clearance.
1.
LOAD ROLLER
2.
WEAR PLUG
3.
RETAINING RING
4.
SETSCREW
5.
JAM NUT
6.
STUB SHAFT
7.
MAST CHANNEL
Figure 24. Load Roller and Wear Plug Assembly
1.
SPECIAL TOOL
2.
ADJUSTMENT HANDLE
3.
WELDMENT
Figure 25. Wear Plugs Adjustment
39
Summary of Contents for MAST N30XMH
Page 14: ...Two Stage Mast Assembly 4000 SRM 482 Figure 10 Two Stage Mast Assembly Dual Lift Cylinders 10 ...
Page 27: ...4000 SRM 482 Three Stage Mast Assembly Figure 18 Three Stage Mast Assembly 23 ...
Page 34: ...Three Stage Mast Assembly 4000 SRM 482 Figure 21 Hose and Cable Assemblies Outer Weldment 30 ...
Page 51: ......
