Manitowoc 1400A User Manual

National Crane 1-21-2019 Control # 104-07 6-11
1400A SERVICE MANUAL SWING
6
Outer Race Torquing
The outer race bolts are located on top of the bearing
(Figure 6-7).
1. Extend and set the outriggers. Fully elevate the boom.
Torque eight bolts (Figure 6-5) to 637 Nm ±27 Nm (470
lb-ft ±20 lb-ft) using the following sequence pattern; 1,
17, 9, 25, 4, 20, 12, and 28. Tools used are the socket,
multiplier, backlash adapter, necessary extensions, and
torque wrench.
2. Return to bolt 1 and torque all bolts sequentially in a
clockwise direction:
Fasteners and Torque Values on
page 1-7. The same tools are used as in step 1.
BEARING CLEARANCE
If a swing bearing exhibits the following symptoms, it may
have reached the end of its useful life.
• metal particles in the grease
• increased drive power required
• noise
• rough operation
• acceleration in the increase in bearing clearance
Measure the internal clearance of the swing bearing to
determine if it needs to be replaced. (Reference National
Crane Technical Support Information TSI #10)
1. Place the boom over the font and set the outriggers.
2. Put a dial indicator (2, Figure 6-8) opposite the boom on
the T-box frame (3).
3. Place the dial on the top of the swing bearing (1,
Figure 6-8).
4. Power the boom down onto the boom rest.
5. Set the dial indicator at zero.
6. Raise the boom about 3 inches above the boom rest.
7. Record the deflection indicated on the dial.
8. Repeat steps 4 through 7 three times and average the
readings.
9. If the average is greater than 0.090 inches, replace the
bearing.
10. If the average is less than 0.090 inches, repeat the
measurement at every 45° around the total working area
of the crane (Figure 6-9).
a. Measure the deflection a positions 2, 3, 7, and 8 for
180° rotation and positions 2 and 8 for 360° rotation.
b. Use another crane to support the end of the boom
when the boom is powered down.
c. Locate the dial indicator opposite the boom.
d. Set the dial indicator to zero.
e. Raise the boom about 3 inches.
f. Record the reading on the dial indicator.
g. Repeat steps d through f three time.
h. Average the readings.
i. If the averages is greater than 0.090 inches at any
position, replace the bearing.
FIGURE 6-7
Outer Race Bolts
1
3
FIGURE 6-8
2
8831
Fo
r
Reference
Only

Manitowoc 1400A Specifications

General

Brand	Manitowoc
Model	1400A
Category	Construction Equipment
Language	English