Exmark Lazer HP Operator's Manual page 45

a) Stop engine, wait for all moving parts to stop, and remove key.
b) Check to make sure the center of the bolt head in the center of the spring
loaded pulley, on left side engine deck support, is positioned between the
centers of the two alignment holes in the left support plate (See Figure 13). It
is necessary to adjust the belt tension when the center of the bolt head is at
or below the center of the bottom alignment hole.
c) When adjustment is necessary, loosen the idler pulley on the right-hand
side so it can move up and down in the slot.
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.
NOTE: When installing a new belt, it is necessary to reposition the right
adjusting pulley upward in the slot 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 Adjust Seat Switch
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
PTO 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" (5.3 cm) (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 PTO engaged, the engine should stop after 1/2
second has elapsed.
b) To adjust seat switch, loosen lock nut 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.
5.2.7 Belt Guide Adjustment.
a) Stop engine, wait for all moving parts to stop, and remove key.
b) Remove the belt shield on the right side of mower deck.
c) Note belt guide bolted to deck near the shield support stud and right-hand
pulley. Guide should be 1/8" (3.2 mm) away from the belt, with bolt-end of
guide near end of slot (See Figure 14).
d) If adjustment is necessary, loosen the bolt securing the belt guide and
make proper adjustment. Tighten hardware.
FIGURE 13
MULE DRIVE BELT ADJUSTMENT
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