Bleeding The Brake System; Towing - JLG T500J Service And Maintenance Manual

SECTION 3 - CHASSIS & TURNTABLE

Bleeding the Brake System

DO NOT USE BRAKE FLUID DRAINED FROM THE BRAKE SYSTEM IN REFILLING
THE MASTER CYLINDER. USED BRAKE FLUID CAN BE CONTAMINATED FROM
THE SYSTEM.
1. Remove the master cylinder filler cap and fill reservoir
with DOT type 3 or 4 automotive brake fluid.
2. Check all hydraulic line fittings and connections to make
sure they are leak free.
3. At brake assembly, connect a bleeder hose to bleeder
fitting on the wheel cylinder and submerge the free end
in a container with brake fluid. DO NOT reuse brake fluid.
NOTE: Use a power bleeder or a bar with a 2" (50 mm) hitch ball
attached. Do not use the breakaway cable for bleeding the
brake system. If a power bleeder is used, air pressure of 35
psi (2.4 Bar) is most effective.
4. Loosen the bleeder fitting at the top of the brake assem-
bly.
5. Apply the actuator and tighten the bleeder fitting.
Return the actuator to the forward position. Again,
loosen the bleeder valve one turn and apply the actua-
tor. Repeat this procedure until fluid expelled from the
bleeder hose is free of air bubbles. It is helpful to lower
the trailer tongue to promote air bubble movement in
the brake tubing. It is also helpful to tap gently along the
brake tubing during the brake bleeding to keep air bub-
bles from sticking to the inside of the brake tubing. Dur-
ing this procedure, the master cylinder reservoir fluid
level must be maintained at no less than 1/2 full and no
more than 1/2" (13 mm) from the top of the reservoir.
6. When no air bubbles are visible, close the bleeder valve
securely and remove the bleeder hose.
7. Repeat steps 1 thru 6 for the remaining brake.
8. After bleeding has been completed, re-check fluid level
in the master cylinder.
3-22

Towing

THE TRAILER MAY DISCONNECT IF NOT PROPERLY SECURED. THE RELEASE
HANDLE MUST BE FULLY CLOSED BEFORE TOWING. DO NOT FORCE THE
RELEASE HANDLE INTO THE CLOSED POSITION.
1. Position the actuator ball socket above the ball.
DO NOT DAMAGE THE ACTUATOR WHEN BACKING UP TOWING VEHICLE FOR
HOOK-UP.
2. Hold the release handle in the open position. Release
handle must be held in fully open position to remove
from or place on ball.
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