COATS 7665 AX/EX Tire Changer - Manual (Page 11)

Figure 19 - Location of Manual Release Valve
PERFORMANCE, CUSTOM, AND ALU-
MINUM WHEELS
Only tire technicians with
experience and training
on custom wheels should
attempt to service expensive custom alloy or
aluminum wheels and high-performance low-
profile tires.
Pre-Operation Notes:
•
Ensure all weights have been removed.
• Clamp wheel from the outside.
• Use ample lubricant for mount and demounting
• Always review wheel nicks and/or scratches
with the owner before servicing.
Performance Tires and Wheels • Demounting
Follow these instructions for performance type tires
and wheels, including run-flat tires and their associ-
ated wheels, and asymmetrical hump wheels.
1. Remove valve core and completely deflate tire.
2. Pull the bead loosener shoe away from the
machine and roll the tire into position against the
bumper pads. Position the tire with the valve
stem in the 2 o'clock position (in direct line with
the bead loosener shoe). Always loosen the
bead on the narrow/mounting side of the wheel
first (Figures 4 and 20).
Figure 20 - Position Tire for Bead Loosening
AA: 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 21). Always loosen the
beads near the valve stem on both sides of rim.
Figure 21 - Asymmetrical Hump Wheel
AB: Some wheels/tires have a low pressure
sensor/transmitter strapped to the wheel (Figure 22).
This is especially true on run-flat tire/wheel systems.
The sensor is positioned directly opposite from the
valve stem. Other low pressure warning systems
have the sensor as part of the valve. To avoid dam-
aging the sensor, always loosen the top bead with
the valve stem at the 2 o’clock position first, then
loosen the bottom bead with the valve stem at the 2
o’clock position, and then continue to loosen the
remaining circumference of the beads as necessary.
Avoid loosening at 180 deg. (opposite) the valve.
Figure 22 - Wheel with Low Pressure Sensor/Transmitter
3. Loosen bottom bead, starting with valve stem at
2 o’clock position next to the loosener shoe
(Figure 23).
Figure 23 - Loosen Bottom Bead
77050/7055/7060/7065 X/EX Rim Clamp Tire Changer • 9
Manual Release Valve
CAUTION
Valve Stem
Smooth
Hump At
Valve
Hole
Ledge
Hump -
Rest of
Wheel
Valve Stem
Sensor
Valve Stem