# Gulfstream Service Bulletin GIIB 32-3: No revision named

- Rights: © Gulfstream Aerospace Corporation. Filed by the FAA in regulations.gov docket FAA-2016-9070, the docket of AD 2016-18-11. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [Gulfstream Service Bulletin GIIB 32-3](https://openairdocs.org/service-documents/gulfstream/giib32-3.md)
- Title as filed: GIIB_32_3 Temp Rev
- Pages: 20
- PDF: https://openairdocs.org/files/sha256/54/0f/540f3328dfaa936c192699ad63feaf4ee6634becfd6fec096579c9febef96aa9
- Page: https://openairdocs.org/service-documents/gulfstream/giib32-3/file/540f3328dfaa

## Text

Each page's text from the PDF; open the PDF at a page with #page=N.

### Page 1

LANDING GEAR DOOR ACTUATORS — REMOVAL / INSTALLATION
1. Nose Gear Door Actuator Assembly — Removal / Installation
A. Preparation
SPECIAL TOOLS AND TEST EQUIPMENT
Protective caps and plugs .................................................................................................. Standar d
Skydrol resistant container ................................................................................................. Stand ard
CONSUMABLES
Backup ring ............................................................................................................. MS28773- 04 (2)
Cotter pin ............................................................................................................... MS24665 -152 (2)
Lubricant ........................................................................................................ MCS-352B (see No te)
Nut ............................................................................................................................. MS17826-5 (2)
O-ring ...................................................................................................................... NAS 1612-4A (3)
NOTE: When lubricant MCS-352B is not available, Skydrol fluid may be used as an alternate.
(1) Reference(s)
• Nose Gear Door Actuator and Door Rod - Adjustments, 32-03-04, Adjustment / Test
(2) Aircraft Preparation
(a) Prepare aircraft for safe ground maintenance.
WARNING: FAILURE TO INSTALL ALL LANDING GEAR AND LANDING GEAR
DOOR SAFETY DEVICES BEFORE WORKING IN ANY WHEEL WELL
MAY RESULT IN SERIOUS INJURY OR DEATH.
FAILURE TO DISSIPATE HYDRAULIC PRESSURE BEFORE
INSTALLING OR REMOVING ALL LANDING GEAR AND LANDING
GEAR DOOR SAFETY DEVICES SHALL CAUSE DAMAGE TO
AIRCRAFT OR MAY RESULT IN SERIOUS INJURY OR DEATH.
FAILURE TO ENSURE ALL PERSONNEL AND EQUIPMENT ARE
CLEAR OF FLIGHT CONTROL SURFACES BEFORE OPERATING
FLIGHT CONTROLS MAY RESULT IN SERIOUS INJURY OR DEATH.
(b) Ensure landing gear doors are open.
(c) Dissipate hydraulic system pressure by cycling flight controls and / or operating brake
pedals several times.
(d) Install all landing gear and landing gear door safety devices.
B. Removal
NOTE: The following procedure is performed in conjunction with Figure 401.
(1) Remove hydraulic lines from nose gear door actuator.
NOTE: Use suitable container to catch hydraulic fluid when removing hydraulic lines.
(2) Install protective caps and plugs on all open ports and lines.
(3) Remove cotter pin, nut, washers, bolt and spacer securing fixed end of actuator to aircraft
structure. Discard cotter pin.
(4) Remove cotter pin, nut, washers and bolt securing actuator rod end. Discard cotter pin.
(5) Remove actuator.
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(6) If actuator is to be replaced, remove and retain hydraulic fittings and restrictor from actuator.
Note position of fittings for installation. Discard O-rings.
C. Installation
WARNING: FAILURE TO INSTALL ALL LANDING GEAR AND LANDING GEAR DOOR
SAFETY DEVICES BEFORE WORKING IN ANY WHEEL WELL MAY RESULT IN
SERIOUS INJURY OR DEATH.
NOTE: The following procedure is performed in conjunction with Figure 401.
(1) If a new actuator is being installed, perform the following:
(a) Apply a thin coat of lubricant to new O-rings.
NOTE: A buildup of lubricant in the O-ring glands may prevent the O-ring from sealing
properly.
(b) Install O-rings on hydraulic fittings retained in Step 1.B.(6).
(c) Install hydraulic fittings in actuator.
(2) Position actuator on aircraft.
(3) Secure fixed end of actuator with bolt, washers, spacer and nut removed in Step 1.B.(3).
(4) Tighten nut and secure with cotter pin.
(5) Secure actuator rod end with bushings, bolt, washers and nut removed in Step 1.B.(4).D on o t
tighten nut or install cotter pin at this time.
D. Follow On
(1) Inspect for presence of foreign objects.
(2) Perform Nose Gear Door Actuator and Door Rod - Adjustments, 32-03-04, Adjustment / Test.
(3) Tighten nut on actuator rod end and install cotter pin.
(4) Remove protective caps and plugs from hydraulic lines.
(5) Install hydraulic lines removed in Step 1.B.(1).
(6) Cycle doors using grounds service valve to verify operation.
(7) Inspect actuator installation for hydraulic leaks.
(8) Record all maintenance actions in accordance with current governing authority.
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Nose Gear Door Actuator Installation
Figure 401
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2. Nose Gear Door Flow Regulator — Removal / Installation
A. Preparation
SPECIAL TOOLS AND TEST EQUIPMENT
Protective caps and plugs .................................................................................................. Standar d
Skydrol resistant container ................................................................................................. Stand ard
(1) Reference(s)
• Landing Gear - Normal and Emergency - Functional Test, 32-00-00, Adjustment / Test
or Code 320310
WARNING: FAILURE TO INSTALL ALL LANDING GEAR AND LANDING GEAR DOOR
SAFETY DEVICES BEFORE WORKING IN ANY WHEEL WELL MAY
RESULT IN SERIOUS INJURY OR DEATH.
FAILURE TO DISSIPATE HYDRAULIC PRESSURE BEFORE INSTALLING
OR REMOVING ALL LANDING GEAR AND LANDING GEAR DOOR
SAFETY DEVICES SHALL CAUSE DAMAGE TO AIRCRAFT OR MAY
RESULT IN SERIOUS INJURY OR DEATH.
FAILURE TO ENSURE ALL PERSONNEL AND EQUIPMENT ARE CLEAR
OF FLIGHT CONTROL SURFACES BEFORE OPERATING FLIGHT
CONTROLS MAY RESULT IN SERIOUS INJURY OR DEATH.
(2) Dissipate hydraulic system pressure by cycling flight controls and / or operating brake pedals
several times.
(3) Install all landing gear and landing gear door safety devices.
(4) Open radome.
B. Removal
(1) Remove hydraulic lines from flow regulator.
NOTE: Use suitable container to catch hydraulic fluid when removing hydraulic lines.
(2) Install protective caps and plugs on all open lines.
(3) Remove flow regulator.
C. Installation
(1) Remove protective caps and plugs on all open lines.
(2) Position T- fitting in narrow end of flow regulator. Ensure that check valve is installed in T-fitting
with flow arrows pointing away from T- fitting.
(3) Install hydraulic lines on flow regulator.
D. Follow On
(1) Inspect for presence of foreign objects.
(2) Perform Landing Gear - Normal and Emergency - Functional Test, 32-00-00, Adjustment /
Test or Code 320310.
(3) Inspect flow regulator installation for hydraulic leaks.
(4) Close radome.
(5) Record all maintenance actions in accordance with current governing authority.
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3. Nose Gear Actuator Up Port Restrictor — Removal / Installation
A. Preparation
SPECIAL TOOLS AND TEST EQUIPMENT
Skydrol resistant container ................................................................................................. Stand ard
CONSUMABLES
Lubricant ........................................................................................................ MCS-352B (see No te)
O-ring ............................................................................................................................ NAS1612-6A
O-ring ............................................................................................................................ NAS1612-4A
NOTE: When lubricant MCS-352B is not available, Skydrol fluid may be used as an alternate.
(1) Reference(s)
• Landing Gear - Normal and Emergency - Functional Test, 32-00-00, Adjustment / Test
or Code 320310
WARNING: FAILURE TO INSTALL ALL LANDING GEAR AND LANDING GEAR DOOR
SAFETY DEVICES BEFORE WORKING IN ANY WHEEL WELL MAY
RESULT IN SERIOUS INJURY OR DEATH.
FAILURE TO DISSIPATE HYDRAULIC PRESSURE BEFORE INSTALLING
OR REMOVING ALL LANDING GEAR AND LANDING GEAR DOOR
SAFETY DEVICES SHALL CAUSE DAMAGE TO AIRCRAFT OR MAY
RESULT IN SERIOUS INJURY OR DEATH.
FAILURE TO ENSURE ALL PERSONNEL AND EQUIPMENT ARE CLEAR
OF FLIGHT CONTROL SURFACES BEFORE OPERATING FLIGHT
CONTROLS MAY RESULT IN SERIOUS INJURY OR DEATH.
(2) Ensure landing gear doors are open.
(3) Dissipate hydraulic system pressure by cycling flight controls and / or operating brake pedals
several times.
(4) Install all landing gear and landing gear door safety devices.
B. Removal
(1) Remove hydraulic line from nose gear door actuator restrictor.
NOTE: Use suitable container to catch hydraulic fluid when removing hydraulic lines.
(2) Remove restrictor.
(3) If restrictor is to be replaced, remove and retain hydraulic fittings. Discard O-rings.
C. Installation
WARNING: FAILURE TO INSTALL ALL LANDING GEAR AND LANDING GEAR DOOR
SAFETY DEVICES BEFORE WORKING IN ANY WHEEL WELL MAY RESULT IN
SERIOUS INJURY OR DEATH.
(1) If a new restrictor is being installed, perform the following:
(a) Apply a thin coat of lubricant to new O-rings.
NOTE: A buildup of lubricant in the O-ring glands may prevent the O-ring from sealing
properly.
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(b) Install O-rings on hydraulic fittings retained in Step 3.B.(3).
(c) Install hydraulic fittings in restrictor.
(2) Install restrictor with free flow arrow pointing towards actuator.
D. Follow On
(1) Perform Landing Gear - Normal and Emergency - Functional Test, 32-00-00, Adjustment /
Test or Code 320310.
(2) Perform leak check.
(3) Inspect for presence of foreign objects.
(4) Record all maintenance actions in accordance with current governing authority.
4. Main Gear Door Actuator Assembly — Removal / Installation
A. Preparation
SPECIAL TOOLS AND TEST EQUIPMENT
Protective caps and plugs .................................................................................................. Standar d
Skydrol resistant container ................................................................................................. Stand ard
CONSUMABLES
Lubricant ........................................................................................................ MCS-352B (see No te)
Cotter pin ............................................................................................................... MS24665 -285 (2)
O-ring ...................................................................................................................... NAS 1612-6A (2)
O-ring ............................................................................................................................ NAS1612-4A
Nut ............................................................................................................................. MS17826-9 (2)
NOTE: When lubricant MCS-352B is not available, Skydrol fluid may be used as an alternate.
(1) Reference(s)
• Landing Gear Cycling - Operational Test, 32-00-00, Adjustment / Test or Code 320306
• Main Gear Door Actuating Cylinder - Adjustment, 32-03-04, Adjustment / Test
• Aircraft Illustrated Parts Catalog, 32-30-00, Fig. 13, Door Actuator Instl, Main Landing
Gear
(2) Aircraft Preparation
(a) Prepare aircraft for safe ground maintenance.
WARNING: FAILURE TO INSTALL ALL LANDING GEAR AND LANDING GEAR
DOOR SAFETY DEVICES BEFORE WORKING IN ANY WHEEL WELL
MAY RESULT IN SERIOUS INJURY OR DEATH.
FAILURE TO DISSIPATE HYDRAULIC PRESSURE BEFORE
INSTALLING OR REMOVING ALL LANDING GEAR AND LANDING
GEAR DOOR SAFETY DEVICES SHALL CAUSE DAMAGE TO
AIRCRAFT OR MAY RESULT IN SERIOUS INJURY OR DEATH.
FAILURE TO ENSURE ALL PERSONNEL AND EQUIPMENT ARE
CLEAR OF FLIGHT CONTROL SURFACES BEFORE OPERATING
FLIGHT CONTROLS MAY RESULT IN SERIOUS INJURY OR DEATH.
(b) Ensure landing gear doors are open.
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(c) Dissipate hydraulic system pressure by cycling flight controls and / or operating brake
pedals several times.
(d) Install all landing gear and landing gear door safety devices.
B. Removal
(1) Remove hydraulic lines from main landing gear door actuator.
NOTE: Use suitable container to catch hydraulic fluid when removing hydraulic lines.
(2) Install protective caps and plugs on all open ports and lines.
(3) Remove cotter pin, nut, washers, bolt and bushings securing actuator lower mount to aircraft
structure. Discard cotter pin.
(4) Remove cotter pin, nut, washers, bolt and bushings securing actuator arm to door control
linkage. Discard cotter pin.
(5) Remove actuator from aircraft.
(6) If actuator is to be replaced, perform the following:
(a) Remove unions from actuator.
(b) If installed, remove elbow from left actuator retract inlet on end cap.
NOTE: The earlier dash number left door actuators may have an elbow installed on
the end cap, refer to Aircraft Illustrated Parts Catalog, 32-30-00, Fig. 13, Door
Actuator Instl, Main Landing Gear for correct installation.
(c) Remove O-rings and discard.
C. Installation
WARNING: FAILURE TO INSTALL ALL LANDING GEAR AND LANDING GEAR DOOR
SAFETY DEVICES BEFORE WORKING IN ANY WHEEL WELL MAY RESULT IN
SERIOUS INJURY OR DEATH.
(1) Remove protective caps and plugs from ports and lines.
(2) If a new actuator is being installed, perform the following:
(a) Apply a thin coat of lubricant to new O-rings.
NOTE: A buildup of lubricant in the O-ring glands may prevent the O-ring from sealing
properly.
(b) Install O-ring NAS1612-4A on No. 4 union.
(c) Install No. 4 union in emergency inlet on end cap gland.
(d) Install O-rings NAS1612-6A on unions and / or elbow (left actuator).
NOTE: The earlier dash number left door actuators may have an elbow installed on
the end cap, refer to Aircraft Illustrated Parts Catalog, 32-30-00, Fig. 13, Door
Actuator Instl, Main Landing Gear for correct installation.
(e) Install No. 6 elbow in retract inlet on end cap (left actuator as required).
(f) Install No. 6 union in retract inlet on end cap, as required.
(g) Install No. 6 union in extend inlet on fixed end of actuator.
(3) Position actuator on aircraft.
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(4) Secure actuator lower mount to aircraft structure with bushings, bolt, washers and nut
removed in Step 4.B.(3).
(5) Tighten nut and secure with cotter pin.
(6) Secure actuator arm to door control linkage with bushings, bolt, washers and nut removed in
Step 4.B.(4). Do not tighten nut or install cotter pin at this time.
(7) If auxiliary hydraulic pump will be used to perform Main Gear Door Actuating Cylinder -
Adjustment, 32-03-04, Adjustment / Test, install hydraulic lines on actuator.
D. Follow On
(1) Inspect for presence of foreign objects.
(2) Perform Main Gear Door Actuating Cylinder - Adjustment, 32-03-04, Adjustment / Test .
(3) Tighten nut on actuator arm to door control linkage and install cotter pin.
(4) Perform Landing Gear Cycling - Operational Test, 32-00-00, Adjustment / Test or Code
320306.
(5) Inspect actuator installation for hydraulic leaks.
(6) Clean any spilled hydraulic fluid from landing gear.
(7) Close main landing gear doors, as required.
(8) Record all maintenance actions in accordance with current governing authority.
5. Main Gear Door Actuator End Cap Fitting — Removal / Installation
A. General
The end cap fitting is installed on the main gear door actuator which is located in the left and right
main wheel well.
B. Preparation
SPECIAL TOOLS AND TEST EQUIPMENT
Aluminum calibration standard .................... 0.008”, 0.020” and 0.040” EDM notches or equivalent
Eddy current unit ...................................................................... Hocking Phasec 2200 or equivalent
Eddy current probe, straight, 2 mm ........................................ 614-034-001, 200 kHz or equivalent
Eddy current probe, 90°, 2 mm ............................................... 614-074-007, 200 kHz or equivalent
Thread file ......................................................................................................... -16UN or equivalent
Torque wrench, 10 - 50 inch-pounds (1.13 - 5.65 Nm) ......................... GSE5100720 or equivalent
Vibro-etching tool / metal impression stamp tool ............................................................... Standard
CONSUMABLES
Data plate ................................................................................................................. 1159F 30042-13
Drive screw ................................................................................................................ MS213 18-1 (4)
Epoxy primer ....................................................................................................... 3012 or equival ent
Epoxy topcoat (clear) .......................................................................................... 3020 or equivalent
Epoxy topcoat (white) .......................................................................................... 3013 or equivalent
Felt wiper ........................................................................................................................ MS28932-1
Gland ................................................................................................. 1159HM20140-3 (as required)
Hydraulic fluid ......................................................................................... Skydrol LD-4 or equivalent
Hydraulic data plate ................................................................................................... 1159H20240 -3
Isopropyl alcohol ................................................................................................................. TT-1-735
Lint free cloth .................................................................................................................. .... Standard
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Lubricant ........................................................................................................ MCS-352B (see No te)
Masking tape ....................................................................................................................... Standard
O-ring ........................................................................................................................ N AS1611-145A
O-ring ................................................................................................................... NAS1611-115A (3)
O-ring ............................................................................................................................ NAS1612-4A
O-ring ............................................................................................................................ NAS1612-6A
Retainer ................................................................................................................. MS2759 5-145 (2)
Retainer ................................................................................................................... 1159HM20183-3
Safety wire ................................................................................................................ MS209 95NC32
Shuttle valve ....................................................................................................................... See Note
Scraper .......................................................................................................................... MS28776-12
Screw ................................................................................................................. NAS1101E3 H12 (4)
Seal ............................................................................................................................. 7217FT-952-T
Snap ring ....................................................................................................................... NAS669-168
Washer ............................................................................................................. NAS1149D0316H( 4 )
NOTE: When lubricant MCS-352B is not available, Skydrol fluid may be used as an alternate.
Door actuators originally equipped with 1159SCH238-5, -7, -9 or -11 shuttle valves may
reuse shuttle valve. See Aircraft Illustrated Parts Catalog, 32-30-00, Fig. 14, Door Actuator
Assy, Main Landing Gear (1159H20264-7, -8, -9, -10, -11 and -12) for correct shuttle valve
configurations.
(1) Reference(s)
• Safety Wire - Standard Practices, 20-70-41, Maintenance Practices
• Main Gear Door Actuator Assembly - Removal / Installation, 32-03-04, Removal /
Installation or Code 323520
• Main Gear Door Actuator - Bench Check, 32-03-04, Adjustment / Test or Code 323525
• Aircraft Illustrated Parts Catalog, 32-30-00, Fig. 13, Door Actuator Instl, Main Landing
Gear
• Aircraft Illustrated Parts Catalog, 32-30-00, Fig. 14, Door Actuator Assy, Main Landing
Gear (1159H20264-7, -8, -9, -10, -11 and -12)
(2) Aircraft Preparation
(a) Prepare aircraft for safe ground maintenance.
(b) Remove main landing gear door actuator from aircraft, if not previously removed. See
Main Gear Door Actuator Assembly - Removal / Installation, 32-03-04, Removal /
Installation or Code 323520 .
C. Removal
NOTE: The following numbers in parenthesi s()a r eu s e di nc o n j u n c t i o nw i t hF i g u r e402.
(1) If removing serialized end cap, perform the following:
NOTE: A serialized end cap will be identi fied by part number or serial number of the door
actuator by one of the following methods:
• Door actuator part number will be 1159H20264-25 for left or 1159H20264-26
for right
• Door actuator part number will be 1159H20264-7 - 1159H20264-24 and door
actuator serial number will end with a C
• Door actuator part number will be 1159H20264-701 - 1159H20264-2101 and
door actuator serial number will end with a C, 1159SB50074 added an 01 to
part numbers 1159H20264-7 - 1159H20264-21
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Serialized end cap should have a part number (1159HM20178-15 for left or -16
for right) and a serial number stamped or etched on end cap. See Figure 403.
(a) Remove drive screws (2) securing door actuator data plate (1) to door actuator end cap
(10). Discard drive screws.
NOTE: Door actuator data plate could be attached to either side of the end cap. Data
plate will have the part number (1159H20264-xx) and serial number of the
door actuator.
(b) Retain door actuator data plate (1) for installation on new end cap.
(2) If removing nonserialized end cap, perform the following:
(a) Locate existing door actuator data plate (1) attached to door actuator end cap (10).
NOTE: Door actuator data plate could be attached to either side of the end cap. Data
plate will have the part number (1159H20264-xx) and serial number of the
door actuator.
(b) Using a vibro-etching or metal impression tool transfer information (MFG BY, PART
NO., SER NO.) from existing door actuator data plate (1) to a new door actuator data
plate.
NOTE: Data plate markings should be vibro-etched or metal impression stamped per
SAE AS478 / MIL-STD-130.
( c ) A d daCt oe n do fdoor actuator serial number on new data plate.
(d) Retain new door actuator data plate (1) for installation on new end cap.
(3) Remove safety wire from collar (4).
(4) Loosen collar (4) and remove locking key (5) securing rod end (6).
(5) Remove rod end (6) and collar (4).
NOTE: Retain rod end, collar and locking key.
(6) Loosen setscrew (7).
(7) Remove safety wire from cylinder nut (8).
(8) Loosen cylinder nut (8) until it turns freely.
(9) Remove safety wire from locking screw (9).
(10) Remove locking screw (9).
(11) Remove end cap (10) from door actuator cylinder body (11).
(12) Inspect threads of door actuator cylinder body (11) where end cap (10) was removed.
(13) If required, clean up threads around index hole for locking screw (9) using thread file.
(14) Remove filings and debris from threads, piston and door actuator cylinder body interior.
(15) Clean threads with lint free cloth and isopropyl alcohol.
(16) Remove shuttle valve (12) from end cap (10) as follows:
(a) Remove safety wire from screws (13), as required.
(b) Remove screws (13) and washers (14) attaching gland (15) to end cap (10). Discard
hardware.
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(c) Remove gland (15) from end cap.
(d) If gland is part number 1159HM20140-1, remove hydraulic union (16) and discard gland
(15).
NOTE: The 1159HM20140-1 gland has a thin (0.125 inch) flange, where the
1159HM20140-3 has a thicker (0.375 inch) flange. See Figure 404.
(e) If gland is 1159HM20140-3, perform eddy current inspection as follows:
NOTE: This procedure is intended to provide trained and experienced NDT
inspectors with the necessary information to perform NDT inspection.
1 Calibrate probe on a 0.020 inch notch to achieve a minimum of a four grid
deflection:
• Mode: Absolute Display: X:Y Gain: 44.0 dB
• Frequency: 150 kHz Phase: 14.0 degrees X: -13.0 dB
• Lo-Pass: DC Hi-Pass: DC
NOTE: These are sample settings. Settings may be changed due to equipment
or operator preferences.
2 Eddy current gland flange, radius and inner diameter of fastener hole for defects.
3 Inspect flange around screw hole and radius of gland, paying particular attention
to areas immediately around fastener hole.
4 Any indication not attributed to edge effect or geometry shall be cause for
replacement of gland.
(f) If gland (15) is retained, remove and discard O-ring (17).
(g) Remove shuttle valve (12).
(h) If shuttle valve is a 1159SCH238-1 or -3, discard shuttle valve (12).
NOTE: Part number is engraved on shuttle valve. Shuttle valve part numbers
1159SCH238-5, -7, -9, and -11 can be reused if no wear or damage is visible.
Refer to Aircraft Illustrated Parts Catalog, 32-30-00, Fig. 14, Door Actuator
Assy, Main Landing Gear (1159H20264-7, -8, -9, -10, -11 and -12) for correct
installation.
(i) If shuttle valve (12) is retained, remove and discard O-rings (18).
(17) Remove union (19) or elbow from end cap (10). Remove O-ring and discard.
NOTE: The earlier dash number left door actuators may have an elbow installed on the end
cap, refer to Aircraft Illustrated Parts Catalog, 32-30-00, Fig. 13, Door Actuator Instl,
Main Landing Gear for correct installation.
(18) Discard end cap (10).
NOTE: Existing O-ring retainers, O-ring, wiper ring, scraper, scraper retainer and retaining
clip / snap ring can be discard with end cap.
D. Installation
NOTE: The following numbers in parenthesi s()a r eu s e di nc o n j u n c t i o nw i t hF i g u r e402.
Installation of a serialized end cap part number 1159HM20178-15 (left) and -16 (right) is
required for tracking the Chapter 5 discard requirement.
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(1) Install new O-rings, retainers, seal, felt wiper, scraper and snap ring in new serialized end cap
(10) as follows:
(a) Apply a thin coat of lubricant to new NAS1611-145A O-ring (20).
NOTE: A buildup of lubricant in the O-ring glands may prevent the O-ring from sealing
properly.
(b) Install MS27595-145 retainer (21), NAS1611-145A O-ring (20) and MS27595-145
retainer (22) in end cap (10).
(c) Soak felt wiper (24) in hydraulic fluid.
(d) Install seal (23), felt wiper (24), scraper (25), 1159HM20183-3 retainer (26) and snap
ring (27) in end cap (10).
(2) Lubricate actuator piston with hydraulic fluid.
(3) Slide end cap (10) over actuator piston.
(4) Thread end cap (10) onto door actuator cylinder body (11) until it bottoms out.
(5) Align end cap (10) with extend inlet (28) on fixed actuator end by backing end cap (10) off up
to one full turn.
(6) Verify that locking screw (9) hole in end cap (10) is aligned with hole in door actuator cylinder
body (11).
NOTE: If locking screw hole is not aligned when end cap is aligned with hydraulic port on
fixed actuator, contact Gulfstream Customer Support for assistance.
(7) Tighten cylinder nut (8) against end cap (10).
(8) Tighten setscrew (7) in locking cylinder nut (8).
(9) Safety wire cylinder nut (8) to end cap (10).
NOTE: See Safety Wire - Standard Practices, 20-70-41, Maintenance Practices .
(10) Install locking screw (9). Torque to 12 - 15 inch-pounds (1.36 - 1.69 Nm).
(11) Safety wire locking screw (9) to end cap (10).
NOTE: See Safety Wire - Standard Practices, 20-70-41, Maintenance Practices .
(12) Install shuttle valve (12) as follows:
NOTE: Only shuttle valve part numbers 1159SCH238-5, -7, -9, or -11 can be used. Only
gland part number 1159HM20140-3 can be used. Refer to Aircraft Illustrated Parts
Catalog, 32-30-00, Fig. 14, Door Actuator Assy, Main Landing Gear (1159H20264-7,
-8, -9, -10, -11 and -12) for correct installation.
(a) Apply a thin coat of lubricant to new O-rings (17, 18).
NOTE: A buildup of lubricant in the O-ring glands may prevent the O-ring from sealing
properly.
(b) Install new NAS1611-115A O-ring (17) on gland (15).
(c) Install new NAS1611-115A O-rings (18) on shuttle valve (12).
(d) Install shuttle valve (12) with threaded center hole facing outward towards gland.
(e) Install gland (15) on end cap (10).
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### Page 13

(f) Install screws (13) and washers (14) on gland (15).
(g) Torque screws (13) to 20 - 25 inch-pounds (2.26 - 2.82 Nm).
(h) Safety wire screws (13) to each other.
NOTE: See Safety Wire - Standard Practices, 20-70-41, Maintenance Practices .
(13) Install union (16) removed in Step 5.C.(16)(d) as follows:
(a) Apply a thin coat of lubricant to new NAS1612-4A O-ring.
NOTE: A buildup of lubricant in the O-ring glands may prevent the O-ring from sealing
properly.
(b) Install NAS1612-4A O-ring on union (16).
(c) Install union (16) in gland (15).
(14) Install union or elbow (19) removed in Step 5.C.(17) as follows:
NOTE: The earlier dash number left door actuators may have an elbow installed on the end
cap, refer to Aircraft Illustrated Parts Catalog, 32-30-00, Fig. 13, Door Actuator Instl,
Main Landing Gear for correct installation.
(a) Apply a thin coat of lubricant to new O-ring NAS1612-6A.
NOTE: A buildup of lubricant in the O-ring glands may prevent the O-ring from sealing
properly.
(b) Install NAS1612-6A O-ring on union or elbow (19).
(c) Install elbow in end cap (10) on left actuator, as required.
(d) Install union (19) in end cap (10), as required.
(15) Ensure actuator piston is fully retracted (bottomed out) in door actuator cylinder body (11).
(16) Install locking key (5) and collar (4) onto rod end (6).
(17) Thread rod end (6) into actuator piston.
(18) With piston bottomed out in actuator adjust rod end (6) to achieve dimension shown in Figure
405.
(19) Tighten collar (4) against piston.
(20) Safety wire collar (4) to locking key (5).
NOTE: See Safety Wire - Standard Practices, 20-70-41, Maintenance Practices .
(21) Apply epoxy primer and topcoat to all bare areas as follows:
NOTE: Avoid applying primer or topcoat to ports, rod end bearing, part number stamp or
exposed piston surfaces.
(a) Tape off around bare areas.
(b) Apply one coat of epoxy primer to all bare areas.
NOTE: Allow sufficient time for epoxy primer to cure.
(c) Apply one coat of white epoxy topcoat to all areas epoxy primer was applied.
NOTE: Allow sufficient time for white epoxy topcoat to cure.
(d) Remove all masking tape.
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### Page 14

(22) Install door actuator data plates as follows:
(a) Install door actuator data plate (1) retained from Step 5.C.(1)(b) or Step 5.C.(2)(d) with
screws (2).
(b) Install new hydraulic warning data plate (3) with screws (2).
(c) Overcoat data plate (1) and hydraulic warning data plate (3) with clear epoxy topcoat.
NOTE: Allow sufficient time for epoxy to cure.
E. Follow On
(1) Inspect for presence of foreign objects.
(2) Perform Main Gear Door Actuator - Bench Check, 32-03-04, Adjustment / Test or Code
323525.
(3) Install main landing gear door actuator. See Main Gear Door Actuator Assembly - Removal /
Installation, 32-03-04, Removal / Installation or Code 323520 .
(4) Record all maintenance actions in accordance with current governing authority.
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### Page 15

28
7
2
3
6
9
11
8
2
1
4 5
DETAIL A
TIL-027719G
10
Main Landing Gear Door Actuator End Cap
Figure 402 (Sheet 1 of 2)
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### Page 16

TIL-027720G
20
DETAIL B
DETAIL C
21
22
23
24
25
26 27
18
18
14
13
15
17
19
16
12
Main Landing Gear Door Actuator End Cap
Figure 402 (Sheet 2 of 2)
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### Page 17

TIL-027721G
Serialized Door Actuator End Cap
Figure 403
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### Page 18

TIL-027722G
1159HM20140-1
1159HM20140-3
0.125 INCHES
0.375 INCHES
Main Landing Gear Door Actuator End Cap Gland
Figure 404
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### Page 19

TIL-027723G
13.006 INCHES
13.056 INCHES
Door Actuator Rod End Adjustment
Figure 405
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### Page 20

6. Main Gear Door Actuator End Cap Fitting — Scrap
A. General
The end cap fitting is installed on the main gear door actuator which is located in the left and right
main wheel well.
Gulfstream recommends a review of the Main Gear Door Actuator - Bench Check, 32-03-04,
Adjustment / Test or Code 323525 procedure, which is a required follow on procedure to the Main
Gear Door Actuator End Cap Fitting - Removal / Installation, 32-03-04, Removal / Installation or
Code 323523, to ensure proper test equipment is available before proceeding.
For main gear door actuator end cap fittings that are not serialized, the end cap fitting must be
tracked by the main gear door actuator part number and serial number until end cap is replaced with
a serialized end cap.
B. Preparation
(1) Reference(s)
• Main Gear Door Actuator Assembly - Removal / Installation, 32-03-04, Removal /
Installation or Code 323520
• Main Gear Door Actuator End Cap Fitting - Removal / Installation, 32-03-04, Removal /
Installation or Code 323523
• Main Gear Door Actuator - Bench Check, 32-03-04, Adjustment / Test or Code 323525
(2) Aircraft Preparation
(a) Prepare aircraft for safe ground maintenance.
(b) Remove main gear door actuator. See Main Gear Door Actuator Assembly - Removal /
Installation, 32-03-04, Removal / Installation or Code 323520 .
C. Procedure
(1) Remove end cap from main gear door actuator. See Main Gear Door Actuator End Cap Fitting
- Removal / Installation, 32-03-04, Removal / Installation or Code 323523 .
(2) Discard main gear door actuator end cap.
(3) Install a serialized end cap part number 1159HM20178-15 (left) or -16 (right) on main gear
door actuator. See Main Gear Door Actuator End Cap Fitting - Removal / Installation,
32-03-04, Removal / Installation or Code 323523 .
D. Follow On
(1) Inspect for presence of foreign objects.
(2) Install main gear door actuator. See Main Gear Door Actuator Assembly - Removal /
Installation, 32-03-04, Removal / Installation or Code 323520 .
(3) Record all maintenance actions in accordance with current governing authority.
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