BigDog Series X, General Service Manual

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REV E 5-4 108936BD_0812
Park brake adjustment
1. Shut engine off, place steering control levers in the park
brake position, disengage deck clutch, remove ignition
switch key and disconnect negative battery cable before
doing any adjustments.
2. Raise the rear of the mower and block with certified jack
stands. The rear wheels need to be able to rotate freely
and clear of all obstructions.
3. Chock the front tires.
4. Position the steering control levers in the neutral position.
NOTE: The front brake link is not to be adjusted. Figure
5-10
5. Open the hydraulic pump’s bypass valve, on the side that
is being adjusted, by turning the bypass valve counter
clockwise one-half to one revolution. Figure 5-11
6. Try and rotate the tire by hand. The tire should rotate.
Remember hydraulic oil resistance will prevent the tire
from rotating freely even with the bypass valves open.
There should be no resistance from the brakes at this
point.
7. Move the steering control lever to where it is just inside
(1/8” [3.175mm]) the park brake slot. Figure 5-12
NOTE: When the steering control lever is against the
outside edge of the slot, the brakes should not be
engaged.
8. Rotate the tire. If the brake is adjusted properly the tire
will still rotate but friction will start to become noticeable
here. However, if no brake resistance is noticed, the brake
needs adjusted as follows:
a. Loosen the brake linkage jam nuts. (Figure 5-13)
Rotate the tire and at the same time rotate the
turnbuckle to shorten the length of the brake linkage
to increase the brake pressure. When you feel the
brake begin to engage, stop adjusting the turnbuckle.
Re-tighten the jam nuts on the turnbuckle.
b. Place the control lever in the park brake slot. The tire
should not rotate when the control lever is in the park
brake position. Figure 5-12
c. Place the control lever in the neutral position. The tire
should rotate freely.
9. Close the hydraulic pump’s bypass valve. Figure 5-11
10. Repeat steps 4 through 9 for the other side.
11. Check to make sure all tools or obstructions are removed
from under the mower.
12. Raise the rear of the mower and remove the jack stands.
Figure 5-9
WARNING
This procedure will require that the unit be raised and
blocked up off of the ground. It is necessary for the
wheels to rotate without coming in contact with the floor
or any object that would permit the unit to propel itself.
Stay clear and exercise caution when rotating wheels to
prevent injury. Use only appropriate vehicle stands, with
a minimum weight rating of 2000 pounds to block the
unit up. Use in pairs only. Follow the instructions sup-
plied with the vehicle stands.
Align steering
control lever
±.125” (3.175mm)
Figure 5-10
Figure 5-11
Brake link
Bypass valve