Tensioning the Blade Drive
Belts
Service Interval:
After the first 10 hours
Every 50 hours
Check the condition and tension of the cutting unit drive belts
initially after 10 hours of operation and every 50 operating
hours thereafter.
When properly tensioned, the inside measurement of the
extension spring (hook to hook) should be approximately
8.9 cm ± .63 cm (3.50 ±0.25 inch). Once the correct spring
tension is attained, adjust the stop bolt (carriage bolt) until
there is approximately 0.32 cm ± 0.152/0.000 cm (0.125
+0.060/-0.000 inch) clearance between the head of the bolt
and the idler arm (
).
Note:
Make sure the belt is positioned on the spring side
of the belt guide (
).
Figure 69
1.
Belt
4.
Belt guide
2.
Eye bolt
5.
Flange nut
3.
Extension spring
6.
Stop bolt
Replacing the Blade Drive Belt
Service Interval:
Every 800 hours
The blade drive belt, tensioned by the spring loaded idler
pulley, is very durable. However, after many hours of use,
the belt will show signs of wear. Signs of a worn belt are:
squealing when belt is rotating, blades slipping when cutting
grass, frayed edges, burn marks and cracks. Replace the belt if
any of these conditions are evident.
1.
Lower the cutting unit to the shop floor. Remove the
belt covers from the top of the cutting unit and set the
covers aside.
2.
Loosen the eye bolt allowing the removal of the
extension spring (
).
3.
Loosen the flange nut securing the stop bolt to the
mounting tab. Back off the nut enough to allow the
idler arm to pass by the stop bolt (
). Move the
idler pulley away from the belt to release belt tension.
Note:
If the stop bolt is ever removed from the
mounting tab, make sure it is reinstalled in the hole that
aligns the stop bolt head with the idler arm.
4.
Remove the bolts securing the hydraulic motor to the
cutting unit (
). Lift the motor off of the
cutting unit and lay it on top of the cutting unit.
Figure 70
1.
Hydraulic motor
2.
Mounting bolts
5.
Remove the old belt from around the spindle pulleys
and idler pulley.
6.
Route the new belt around the spindle pulleys and idler
pulley assembly.
7.
Position the hydraulic motor on the cutting unit after
routing the belt around the pulleys. Mount the motor
to the cutting unit with the bolts previously removed.
Note:
Make sure the belt is positioned on the spring
side of the belt guide (
8.
Reconnect the extension spring (
) to the eye
bolt and tension the belt as follows:
•
When properly tensioned, the inside measurement
of the extension spring (hook to hook) should be
approximately 8.9 cm ± 0.63 cm (3.50 ±0.25 inch).
•
Once the correct spring tension is attained,
adjust the stop bolt (carriage bolt) until there is
approximately 0.32 cm ± 0.152/0.000 cm (0.125
+0.060/-0.000 inch) clearance between the head of
the bolt and the idler arm.
50