National Mower HYDRO HYD70OM-8/99 - Manual (Page 21)

NATIONAL HYDRO 70" TRIPLEX ®
21
8.17—COUPLING ALIGNMENT
To prevent coupling failures proper shaft alignment
between the pump shaft and engine shaft is
required. Following these steps will ensure proper
alignment.
1. Remove flex coupling disk (Part# 591181) from in-
between coupling halves.
2. Rotate both coupling halves to a vertical position to
check up and down alignment.
3. Loosen the four fasteners mounting the hydraulic
motor to the frame.
4. Rotate the hex adjuster (counter clockwise to raise,
clockwise to lower) to achieve the proper height of
the hydraulic motor pump shaft. It is recommended
to check alignment on the rounded surfaces of the
couplings.
5. Tighten hydraulic pump mounting fasteners.
Recheck alignment.
6. To adjust forward and back alignment, rotate
couplings 90° to a horizontal position and loosen
the four fasteners mounting the engine to the
frame.
7. Slide engine forward and back until proper
alignment is achieved. Retighten fasteners.
8. Remount coupling disk. (Use of a thread locking
formula is recommended).
COUPLING
HALVES
HEX
ADJUSTER
BELT REPLACEMENT, Continued
1, Gently roll the pivot bracket off of the cutting unit.
Now the belts can easily be removed from the reel
pulleys.
2. Remove the top two bolts on the rear cutting unit
(right side only) pivot bracket. (Noting this bracket
is under spring pressure). Loosen the bottom bolt
and use it as a pivot point. Roll back the pivot
bracket allowing the spring pressure and belt
tension to be released. (Use of a crescent wrench
to get extra leverage is very helpful). Remove belt
from rear cutting unit pulley.
3. To remove belts from the tractor you must remove
the left front cover to access the main engine drive
belts. Remove the front belt guide on the engine
drive pulley, with clutch disengaged, the two main
drive belts and the left wing cutting unit belt, can
now be removed.
4. Removal of the right wing and rear cutting unit belts
can be done by removing the two capscrews
holding the bearing mounting bracket in place.
With capscrews removed rotate the bearing and
bracket creating space to remove both belts.
For reinstallation of new belts reverse these
steps. Taking care to tighten all mounting fasteners and
making sure all belts, pulleys, and pulley scrapers are
all in alignment.
REMOVE
FASTENERS
ROTATE BEARING
AND BRACKET
FOR BELT REMOVAL