Combination Coupler; Bleeding The Brake System; General Maintenance; Servicing The Emergency Lever - JLG T500J Service And Maintenance Manual

SECTION 3 - CHASSIS & TURNTABLE
3.9

COMBINATION COUPLER

THE WEIGHT RATING OF THE COUPLER IS DEPENDENT UPON THE CORRECT
BOLTS BEING USED. USE THE BOLTS PROVIDED WITH THE COUPLER. IF BOLTS
ARE MISSING, REFER TO THE PARTS MANUAL AND OBTAIN REPLACEMENT
BOLTS OR USE THE EXACT SIZE, GRADE, AND NUMBER OF BOLTS AS SPECI-
FIED. USING THE WRONG SIZE, GRADE, OR NUMBER OF BOLTS WILL REDUCE
THE WEIGHT RATING OF THE COUPLER AND COULD CAUSE SEPARATION OF
THE MACHINE FROM THE TOW VEHICLE.

Bleeding the Brake System

1. Remove the bolts and lockwashers that hold the lever
guide and flat emergency lever spring.
2. Remove the lever guide and emergency lever spring.
Using short strokes, pull forward on the emergency
lever, pumping the master cylinder until brake fluid
within the master cylinder stops bubbling.
3. Attach a bleeder hose to the bleeder valve on one of the
wheels and submerge the other end of the hose into a
transparent container partially filled with brake fluid.
4. Loosen the bleeder valve one turn, and while watching
the hose in the container, use the emergency lever to
pump the master cylinder as long as air bubbles con-
tinue to leave the hose. When bubbles stop, close the
bleeder valve and repeat the process on the other
wheel.
NOTE: Check the fluid level in the master cylinder frequently while
bleeding the brakes. Refill as necessary.
5. Once bleeding is completed, refill the master cylinder
and attach the cap securely.
6. Replace the emergency lever spring, lever guide, lock-
washers, and bolts.
7. Test the brakes by pulling the emergency lever forward
until it locks into its second notch position (the lever
should be approximately straight up).
8. Attempt to rotate the wheels in a forward direction. If
any wheels rotate, the brakes must be adjusted. To
adjust the brakes, release the emergency lever from the
locked position, set each wheel's brake adjustment up 2
or 3 notches.
9. Repeat the test procedure as necessary.
3-26

General Maintenance

1. Frequently check brake fluid level. Fluid must be
approved, clean, and uncontaminated.
2. Make sure actuator mounting bolts are secure.
3. Inspect the actuator and replace any bent, worn, or
damaged parts.
4. Be constantly aware of the system's braking quality,
make periodic checks. Consult a certified brake special-
ist to make necessary adjustments or repairs.

Servicing the Emergency Lever

If the emergency lever of the actuator is applied, it can be dis-
engaged by using a screwdriver to lift upward on the front of
the flat emergency lever spring while pulling the lever forward
until it is released. A thorough inspection of the emergency
lever, emergency lever spring, and cable with S-hooks is
required. Damaged parts must be replaced as outlined below:
1. Remove the master cylinder and push rod assembly. Be
careful not to get dirt into the master cylinder. A new
master cylinder gasket should be used when reinstalling
the master cylinder.
2. Remove the cable S-hook from the emergency lever,
emergency lever guide and flat emergency lever spring,
then pull the lever out of the actuator outer case
through the cross-slot in the top.
3. Install the new emergency lever through the cross-slot
in top of the outer case. Attach a new emergency lever
spring and emergency lever guide.
4. Insert the S-hook on the emergency cable into the hole
in the emergency lever and squeeze shut.
5. Add adequate brake fluid to the master cylinder and
bleed the brake system.
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