A AMM - MAIN GEAR SPHERICAL BEARING - REMOVAL/INSTALLATION

Transcription

1 MAIN GEAR SPHERICAL BEARING - 1. Equipment and Materials CHECK THAT THE LANDING GEAR GROUND SAFETIES INCLUDING WHEEL CHOCKS ARE IN POSITION. BEFORE APPLYING OR RELIEVING HYDRAULIC SYSTEM PRESSURE, MAKE CERTAIN THAT THE TRAVEL RANGES OF THE CONTROL SURFACES ARE CLEAR. BEFORE PRESSURIZING HYDRAULIC SYSTEMS, CHECK THAT ALL CONTROLS ARE SET TO CORRESPOND WITH THE ACTUAL POSITION OF THE SERVICES THEY OPERATE. BEFORE POWER IS SUPPLIED TO THE AIRCRAFT MAKE CERTAIN THAT ELECTRICAL CIRCUITS UPON WHICH WORK IS IN PROGRESS ARE ISOLATED. BEFORE PRESSURIZING HYDRAULIC SYSTEMS MAKE CERTAIN THAT HYDRAULIC SYSTEM UNDER MAINTENANCE HAS BEEN ISOLATED. item designation A. 98A Wrench B. Circuit Breaker Safety Clips C. Access Platforms (2.6 m m) (8 ft ft. 10 in.) D. Warning Notices E. Safety Barriers F. Material No Common Greases (Ref ) ) G. Not Applicable H. Not Applicable G. Material No Anti-Corrosion Compound H. Material No Special Materials (Ref ) ) J. Material No Sealants (Ref ) ) K. Material No Cleaning Agents (Ref ) ) Page 1 of 10

2 item designation L. Material No A Storage Preservation (Ref ) ) M. Lockwire - Corrosion Resistant Steel, Dia. 0.8 mm (0.032 in.) L. Material No Cleaning Agents (Ref ) ) M. Material No A Cleaning Agents (Ref ) ) N. Material No A Storage Preservation (Ref ) ) P. Lockwire - Corrosion Resistant Steel, Dia. 0.8 mm (0.032 in.) Referenced Procedures - (Ref , P. Block 0 ) - (Ref , P. Block 0 ) - (Ref , P. Block 301 ) - (Ref , P. Block 301 ) - (Ref , P. Block 501 ) - (Ref , P. Block 401 ) - (Ref , P. Block 301 ) - (Ref , P. Block 501 ) Jacking for Aircraft Maintenance Operations Hydraulics Main Hydraulic Power-Pressurization/ Depressurization Hydraulic Reservoir Pressurizing System Landing Gear Main Gear Leg Main Gear Main Door - (Ground Door(s) Opening) Normal Extension and Retraction 2. Procedure Page 2 of 10

3 A. Job Set-Up (1) On panel 4VU - make certain that landing gear control lever is in DOWN position and prohibit its operation by displaying a warning notice. (2) Between First Officer's and Third Occupant's seats - make certain that landing gear Free Fall extension control handle is in Normal position. (3) Position access platforms. (4) Position safety barriers prohibiting access to gear door travel ranges. MAKE CERTAIN THAT THE DOOR TRAVEL RANGES ARE CLEAR. (5) Open main gear doors (Ref , P. Block 301 ). (6) Depressurize Green hydraulic system (Ref , P. Block 301 ) and prohibit its pressurization by displaying a warning notice : - on Green hydraulic system ground connectors, - on panel 427VU to prohibit operation of Green electric pumps (ELEC PUMPS pushbutton switch). (7) Depressurize Yellow hydraulic system (Ref , P. Block 301 ) and prohibit its pressurization by displaying a warning notice : - on Yellow hydraulic system ground connectors - on panel 427VU to prohibit energization of TRANSF unit (RH PTU pushbutton switch). (8) Depressurize Green and Yellow hydraulic reservoirs (Ref , P. Block 301 ) and prohibit their pressurization by displaying a warning notice : - on panel 429VU to prohibit APU starting, - on reservoir pressurization connector. (9) Open, safety and tag the following circuit breakers : PANEL SERVICE IDENT. LOCATION 128VU LDG GEAR PROX DET & RELAYS LINE 803 N69 to N73 Page 3 of 10

4 PANEL SERVICE IDENT. LOCATION PRIOR TO OPENING CIRCUIT BREAKER 119GB LOCATED ON PANEL 128VU. TAKE THE APPROPRIATE SAFETY PRECAUTIONS (Ref , P. Block 501 ) ). 128VU BRAKES LINE 804 M70 to VU ELEC/PUMPS/WARN/ & CTL 4GE 801/R70 128VU ACCU PRESS/CTL & / CARGO DOOR/PUMP 7GX 802/P70 (10) Jack up aircraft until wheels are clear of ground (Ref , P. Block 001 ). (11) Remove main gear (Ref , P. Block 401 ). B. Removal FED , , , , (Ref. Fig. 401 ) Do not remove accessories from landing gear. Prior to removing the trunnion from the spherical bearing do not omit to remove screws (1) and seal (8) and lubricator nipple (5) to avoid damaging them. POST SB for A/C , , , , (Ref. Fig. 402 ) (1) Cut and remove lockwire and remove screws (11), lockplates (10) and locking ring (9). (2) Make certain that grease nipple (5) is removed from bearing housing (2). Page 4 of 10

5 (3) Remove three screws (3) then using wrench 98A unscrew bearing housing (2). (4) Remove spherical bearing (4) housing. (5) Remove grease seal (6) then shim (7). C. Preparation of Replacement Component (1) Depreserve replacement spherical bearing by removing external protective coverings. (2) Clean with Cleaning Agent (Material No ), all parts retained for installation, check condition then dry with filtered compressed air. Clean the attachment hardware with Cleaning Agent (Material No A) and dry with filtered compressed air. Apply a light coat of Anti-corrosion Compound (Material No ) to the threads of all nuts, screws, bolts and pins. POST SB for A/C , , , , (3) Clean the split faces of housing (2) with Cleaning Agent (Material No or No A). D. Installation (1) Install spherical bearing (4) in housing (2). CAUTION : SPHERICAL BEARING (4) MUST BE POSITIONED WITH GREASE SEAL (6) GROOVE AT THE FORWARD SIDE AND BORE GROOVE POSITIONED IN ORDER TO COINCIDE WITH EXISTING GREASE HOLES. POST SB for A/C , , , , Before assembly, apply a coat of Anticorrosion Compound (Material No or No ) on split faces of housing (2). Remove excess material. Upon assembly, fill spherical bearing housing greaseways with Grease (Material No ). Page 5 of 10

6 (2) Smear grease seal (6) groove with Grease (Material No ). (3) Install a new grease seal (6) on spherical bearing. (4) Install shim (7). (5) Smear threads of bearing housing (2) and threads of housing retaining nut with Anti-corrosion Compound (Material No ). (6) Smear landing gear trunnion and bearing housing (outer ring) (2) with Anti-corrosion Compound (Material No ). (7) Install spherical bearing (4), housing (2) assembly. (8) Fully tighten housing (2) using wrench 98A After tightening housing, make certain that split in housing lies within ± 23 of A/C horizontal plane. If split in housing lies outside ± 23 of A/C horizontal plane, remove housing and either remove shim (7) or adjust shim (7), whichever is necessary, to meet housing split angular requirement. If shim (7) is used, shim min. thickness is In. (0.355mm) and shim max thickness is In. (1.27mm). During reinstallation, a single packer may be installed instead of peelable shim (7). Page 6 of 10

7 E. Test (9) Re-install housing (2) (Ref. Para. 2.D.(5)(6)(7)(8)). (10) Blank three remaining greaseway holes with screws (3) and leave grease nipple (5) hole free. (11) Make certain that spherical bearing moves freely in housing. (12) Apply a bead of Sealant (Material No ) on aft face of housing split line. (13) Install locking ring (9), position lockplates (10) and install screws (11). Wirelock screws (11). (14) Spray Protective Compound (Material No A) over head of housing and on housing retaining nut (as it is possible through the bearing ball bore). (15) Install main gear (Ref , P. Block 401 ). With trunnion installed in its spherical bearing, install seal (8) and screws (1). Install grease nipple (5) in lower of the two greaseway holes (inboard). (1) Perform landing gear extension/retraction test (Ref , P. Block 501 ). F. Close-Up (1) Make certain that working area is clean and clear of tools and miscellaneous items of equipment. MAKE CERTAIN AREA UNDER THE AIRCRAFT IS CLEAR. (2) Lower the aircraft onto its wheels (Ref , P. Block 001 ). (3) Remove safety clips and tags and close circuit breakers 4GE and 7GX, BRAKES circuit breakers, line 804, panel 128VU and LDG GEAR PROX DET & amp; RELAYS, line 803, panel 128VU. AFTER CLOSING CIRCUIT BREAKER 119GB LOCATED ON PANEL 128VU, PERFORM APPROPRIATE PROCEDURE (Ref , P. Block 501 ). Page 7 of 10

8 (4) Lubricate spherical bearing (Ref , P. Block 001 ). (5) Pressurize hydraulic reservoirs (Ref , P. Block 301 ). MAKE CERTAIN THAT DOOR TRAVEL RANGES ARE CLEAR. (6) Close main landing gear doors (Ref , P. Block 301 ). (7) Replenish hydraulic reservoirs as necessary (Ref , P. Block 001 ). (8) Remove warning notices. (9) Close access doors, remove access platforms and safety barriers. (10) Remove all ground handling and maintenance equipment standard and special tools, together with ground power Page 8 of 10

9 and replenishing equipment, all access equipment and miscellaneous items. FED , , , , Figure 401 Figure 401. FWD Spherical Bearing (Sheet 1) Page 9 of 10

10 Figure 402 Figure 402 (Sheet 1) Page 10 of 10