Exmark Lazer Z Operator's Manual page 36

Place a wrench on the 3/8" nut in the center of the spring loaded pulley
and apply upward pressure to relieve tension on the spring (a 1/2" drive
breaker bar and 9/16 socket works best).
Reposition the adjusting pulley to the bottom of the slot. It is necessary to
reposition the right adjusting pulley upward in the slot when installing a new
belt, in order to position the center of the spring loaded pulley between the
alignment holes.
5.2.5 Deck Belt Tension.
a) The deck belt is tensioned by a self-tensioning idler, no adjustment is
necessary.
5.2.6 Alternator belt tension.
a) Stop engine and remove key.
b) To tighten alternator belt, loosen both upper and lower alternator
mounting bolts. Rotate alternator out, away from engine and re-tighten
hardware to secure in place.
c) When properly tensioned, the alternator belt will deflect 1/8" while
applying 5-7 pounds of force to the belt midway between the sheaves.
5.2.7 Adjust Seat Switch (All units except Kohler 26 HP EFI)
a) If necessary, adjust the seat actuator rod length to where the machine will
shut off when the operator raises off the seat (with brake disengaged or blade
switch engaged) but will continue to run with operator in seat (a slight shift
in weight should not shut machine off). Normal adjustment is when length of
spring is 2.09" (with seat up).
NOTE: To prevent rough ground cut-outs the unit is equipped with a time
delayed seat switch. When the operator raises off the seat with either the
brake disengaged or the cutting blades engaged, the engine should stop
after 1/2 second has elapsed.
b) To adjust seat switch, loosen locknut on bottom of the actuator rod (5/16 x 7"
bolt) and adjust the nuts to move the actuator plate up or down on the rod.
5.2.8 Belt Guide Adjustment.
a) Stop engine and remove key.
b) Remove the belt shield on the right side of mower deck.
c) For 52" & 62" units only - note belt guide bolted to deck near the shield
support stud and right-hand pulley. Guide should be 1/8" away from the
belt, with bolt-end of guide at end of slot (See Fig 10).
d) If adjustment is necessary, loosen the bolt securing belt guide and make
proper adjustment. Tighten hardware.
FIG. 9
MULE DRIVE BELT ADJUSTMENT
(Kawasaki Liquid-cooled units only)
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