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(c) After 1 hour, the pressure drop must be less than 650 psi.
(d) After 12 hours, the brake pressure that remains must be more
than 1300 psi.
NOTE:____ You can read the brake pressure from the brake pressure
gage in the flight deck, or the gage on the parking
brake accumulator.
S 735-120
(16)
If the pressure drop is more than permitted, maintenance is not necessary until the next maintenance period if you have the conditions that follow:
(a)
With the parking brake set, the pressure drop for the parking brake accumulator is less than 800 psi in the first 30 minutes.
(b)
With the parking brake released, the pressure drop for the parking brake accumulator must be less than 300 psi in the first 30 minutes.
(c)
If the pressure drop is more than permitted and maintenance is necessary, do the steps that follow: 1) With the parking brake set, make sure that the nitrogen
precharge gas lines for the parking brake accumulator do
not leak. Do a check for leaks as follows:
a) Use a soapy water solution to find leaks at all the fittings, from the precharge fill port to the parking brake accumulator. b) If the fittings on the one inch nitrogen parking brake line leak, do steps 2) through 8).
2) Deparessurize the right hydraulic system.
3) Release the parking brake.
4) Push in the brake pedals seven to eight times to release
the pressure from the parking brake acccumulator.
CAUTION:_______DO NOT LOOSEN THE CHARGING VALVE. INTERNAL PRESSURE COULD BLOW THE VALVE OUT. THIS CAN CAUSE INJURY TO PERSONS OR DAMAGE TO EQUIPMENT.
5) Loosen the fitting one turn on the one inch compressed gas line that leaks and release the accumulator gas prechanrge.
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6) Tighten the leaking fitting on the one inch compressed gas line per the instructions for tightening flareless tubing fittings in AMM 20-10-09/401, Installation of Flareless Fittings in Pressurized Areas, Struts, Fuel Tanks, or Cargo Areas.
NOTE: Make sure that you apply the applicable thread
____ compound to the flarelesss tubing fitting threads as specified in 20-10-09 before you tighten the fittings as specified in 20-10-09.
7) Service the accumulator (AMM 12-15-04/301).
8) Do the leak test again.
9) Do the Parking Brake System Test again.
S 865-121
(17)
Fully push the two brake pedals and release them to disengage the parking brake.
S 215-134
(18)
Make sure the PARK BRAKE light, on the P10 panel, goes off.
S 865-146
(19)
Make sure that the parking brake handle has returned freely to the OFF position.
S 215-144
(20)
GUN 051; Make sure the parking brake ON light on the control housing panel, P62, on the nose landing gear, goes off.
S 215-136
(21)
Observe that the brakes release by observing brake wear indicator pins or movement.
F.
Put the Airplane Back to Its Usual Condition
(1)
Remove pressure from the right hydraulic system (Ref 29-11-00/201).
S 865-150
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S 495-112
WARNING:_______OBEY THE REMOVAL PROCEDURE FOR THE DOOR LOCKS. THE DOORS OPEN AND CLOSE QUICKLY. THE MOVEMENT OF THE DOORS CAN CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT.
(2)
Remove the door locks from the landing gear doors and close the doors (AMM 32-00-15/201).
S 865-113
(3)
Remove electrical power if it is not necessary (Ref 24-22-00/201).
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PARKING BRAKE LEVER/CABLE - REMOVAL/INSTALLATION
________________________________________________
1. General_______
A. This procedure contains two tasks. The first task removes the lever and the cable assembly for the parking brake. The second task installs the lever and the cable assembly for the parking brake.
TASK 32-44-01-004-001
2. Remove the Lever and the Cable Assembly for the Parking Brake (Fig. 401)_____________________________________________________________
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