COATS 50xx Series Tire Changer - Manual (Page 12)

AD: Wheels with an asymmetrical hump have a
larger "ledge" type hump around the wheel
except at the valve hole making them more
difficult to mount and demount (Figure 22).
Figure 22 - Asymmetrical Hump Wheel
AE: Some wheels have a low pressure
sensor/transmitter strapped to the wheel. This is
especially true on run-flat tire/wheel systems. The
sensor is positioned directly opposite from the valve
stem. To avoid damaging the sensor, always loosen
the top bead at the valve stem first, then loosen the
bottom bead at the valve stem, and then continue to
loosen the remaining circumference of the beads as
necessary (Figure 23).
Figure 23 - Wheel with Low Pressure Sensor/Transmitter
3. Loosen bottom bead, starting with valve stem
positioned directly next to the loosener shoe
(Figure 24).
Figure 24 - Loosen Bottom Bead
4. Liberally lubricate the bottom bead of the tire
(Figure 25).
Figure 25 - Lubricate Bottom Bead
5. Clamp the wheel to the table top as described in
items AB and AC on page 9. Always clamp
custom wheels from the outside.
6. Lubricate upper bead liberally. Use the bead
lifting tool to help push the tire bead down so
bead area is easier to reach for lubrication
(Figure 26).
Figure 26 - Lubricate Upper Bead
7. Move swing arm into place and adjust as
described on page 4, steps 7, 8, and 9. Increase
the distance between the demount head and the
wheel an additional 1/16 to 1/8 inch with the
adjustment knob. Locate the valve stem directly
under the demount head before proceeding
(Figure 27).
Figure 27 - Position Valve Stem Under Demount Head
8. Insert bead lifting tool between knob on
demount tool and tire bead. Pull lifting tool down
over wheel to lift bead up and over the knob
(Figure 28).
AF: On asymmetrical hump wheels and stiff
sidewall performance tires, it may be necessary
to use 2 optional drop center tools (part
#435685) to hold tire in the drop center so that
the bead can be lifted over the demount tool.
10 • COATS 50xx Series Rim Clamp Tire Changers
Smooth
Hump At
Valve
Hole
Ledge
Hump -
Rest of
Wheel
Valve Stem
Sensor
Valve Stem
Demount Head
Valve Stem