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Replacement Procedure
1. Remove the left and right upper arm covers.
2. Remove the upper arm back cover.
3. Remove the lower arm rear cover.
Figure 2 - Z-Home Flag With Index Mark
4.
Using a permanent marker, mark a common index mark on both the z-home flag and the upper
arm body as shown in Figure 2 above.
Figure 3 - Lower Z-Shaft Drive Pulley
5. Place an index mark on the lower z-shaft drive pulley and the lower arm body as shown in Figure
3 above.
6. With the machine turned off, slowly loosen the idler pulley screw and rotate the idler pulley
counter clockwise to remove the tension on the belt and then remove the belt.
7. Place the new belt on the upper and lower shaft pulleys, keeping both pulleys aligned to their
respective index marks as shown in Figures 2 and 3 above.
8. Place the belt on the z-motor drive pulley.
CAUTION!!
The head must be timed at this point. Check head timing using the procedures pre-
scribed in “Head-Up Position Adjustment”.
9. Position the belt over the idler pulley (Figure 1) and slowly rotate the idler pulley clockwise until
the belt is tensioned and then tighten the screw on the idler pulley to the torque specifications.
Check and make sure the head is timed using the procedures prescribed in Head-Up Position
Alignment.
CAUTION!!
Improper tensioning of belts can cause internal damage to the machine. Tension
belts carefully and accurately.
10. Check and adjust the tension of the z-belt as prescribed in “Z-Drive Belt Tensioning”.
11. If you are do not have any more repairs to do to the machine, replace the machine covers in the
reverse order they were removed.
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