Diamond Aircraft Industries GmbH N. A. Otto-Straße 5 A-2700 Wiener Neustadt WI-RSB 42-089 WI-RSB 42NG-017 Revision 1 Page 1 of 8 05-Feb-2013


# WORK INSTRUCTION WI-RSB 42-089 WI-RSB 42NG-017

I GENERAL INFORMATION

I.1 Subject Replacement of main landing gear damper seals to allow a greater temperature range.

I.2 Reference Documents DA 42 Series Airplane Maintenance Manual, Doc. No. 7.02.01, latest effective issue. DA 42 NG Airplane Maintenance Manual, Doc. No. 7.02.15, latest effective issue.

I.3 Remarks a) The work must be carried out by a certified aircraft service station or a certified aircraft maintenance mechanic. b) All works, in particular that which is not especially described in this work instruction, must be carried out in accordance with the referenced maintenance manual. c) For conversion factors between SI and US/Imperial units refer to AMM Chapter 02. d) It is recommended to print this Work Instruction in color. e) This Work Instruction including material and labor effort, relate to work on one MLG damper only. f) In case of doubt, contact Diamond Aircraft Industries GmbH.


## II DRAWINGS, SPECIAL TOOLS & MATERIALS

II.1 Drawings
D60-3277-10-00_01

II.2 Special Tools Centering pin X00-W027-00-00.01 Rev."-" Spacer X00-W027-00-00.02 Rev."-" Damper Drain Tool D60-3277-10-00-ST or equivalent Seal pick D60-3277-10-01-ST or equivalent

II.3 Material Quantity Part No. Description 1 D60-9032-77-01 Tandem Seal 1 ORAR00227-N7083 O-Ring 1 ORAR00224-N7083 O-Ring 1 MS 28775-010 O-Ring 1 LN9348 M8 Hexagon nut 1 LN9348 M6 Hexagon nut 100ml 1U-9891 or equivalent Additiv 1U-9891 Caterpillar Inc.Diamond Aircraft Industries GmbH N. A. Otto-Straße 5 A-2700 Wiener Neustadt WI-RSB 42-089 WI-RSB 42NG-017 Revision 1 Page 2 of 8 05-Feb-2013

Materials including special tools are available from Diamond Aircraft Industries.

Note This list includes material only for one damper.

II.4 Consumables Quantity Part No. Description 1l 3627020L Aero Shell Fluid 41 a. r. Royoco 81MS Grease Royoco 81MS a. r. N000 148 or equivalent Acetone

Consumables may be procured locally or from Diamond Aircraft Industries



## III INSTRUCTIONS
1 Ensure AMM-TR-MÄM-42-368 is incorporated into the AMM.

2 Remove the Main Landing Gear Damper acc. to AMM section 32-10.

3 Release nitrogen and oil from the damper.

WARNING: Do not spill Fluid 41 on your skin or on your clothes. Fluid 41 is harmful and can cause skin disease and damage to clothes.

WARNING: The damper is gas loaded. Always wear safety glasses.

Install the adapter with drain hose onto the charging valve of the damper and release the pressure into the suitable container acc. to picture 1.

Wait until the nitrogen is fully released. Push in the damper to minimum position to drain the oil.

Picture1 4 Remove the charging valve from damper.

5 Remove the bottom cap:

 Remove the bolt holding the bottom cap.

 Pull the bottom cap from the damper assembly.Diamond Aircraft Industries GmbH N. A. Otto-Straße 5 A-2700 Wiener Neustadt WI-RSB 42-089 WI-RSB 42NG-017 Revision 1 Page 3 of 8 05-Feb-2013

WARNING: Do not spill Fluid 41 on your skin or on your clothes. Fluid 41 is harmful and can cause skin disease and damage to clothes.

Note: Catch the residual oil into a suitable container.

 Clean the cap with acetone.

 Replace the O-Ring from the cap by new O-Ring ORAR00227-N7083 and apply a coat of Additive 1U-9891 on the new O-Ring.

Caution: Do not use steel tools when removing the O-Ring. Do not scratch the surfaces of the groove.

6 Disassemble piston:

Remove the nut on the piston and pull out the piston end plate. 7 Remove the cylinder tube from the piston.

8 Remove the upper cap from the piston. Clean the upper cap with fresh acetone. Replace the O-Ring from the upper cap by new O-Ring ORA AR 00224-N7083 and apply a coat of Additive 1U-9891 on the new O-Ring.

Caution: Do not use steel tools when removing the O-Ring. Do not scratch the surfaces of the groove.

9 Remove the quad ring and the two backup rings from the tube:

Caution: Do not use steel tools when removing the quad ring. Do not scratch the surfaces of the groove.

Use seal pick D60-3277-10-01-ST to remove the quad ring. Clean the cylinder tube with acetone. Examine the grooves of the cylinder tube and the piston tube for scratches and wear. If scratch and wear are discernible, replace the defective part.

Picture 2Diamond Aircraft Industries GmbH N. A. Otto-Straße 5 A-2700 Wiener Neustadt WI-RSB 42-089 WI-RSB 42NG-017 Revision 1 Page 4 of 8 05-Feb-2013

10 Description of the new tandem seal kit in the cylinder tube:

Support- ring Seal ring Seal base

Picture 3

Pay attention to mounting direction.

11 Install the support ring. Deform the ring carefully acc. to picture 4.

CAUTION Avoid excessive bending of the support ring.

Picture 4

12 Install the seal base below the support ring: Deform the seal base acc. to picture 5 and install it in the cylinder tube. Press the seal base into the groove.

Picture 5 Support ring (Step 1)

Seal base (Step 2) Seal ring (Step 3) TOP

Cylinder tube

Support- ring (Step 1)

Seal base (Step 2)Diamond Aircraft Industries GmbH N. A. Otto-Straße 5 A-2700 Wiener Neustadt WI-RSB 42-089 WI-RSB 42NG-017 Revision 1 Page 5 of 8 05-Feb-2013

13 Install the seal ring into the seal base. Deform the seal ring acc. to picture 6 and install it into the cylinder tube.

CAUTION: Avoid excessive bending of the seal ring. Do not crack the seal ring.

Press the seal ring into the seal base groove.

Picture 6 14 Apply a coat of Additive 1U-9891 on the tandem seal kit and the centering pin.

15 Carefully insert the centering pin X00-W027-00-00.01 into the cylinder tube 2 or 3 times to position the tandem seal in the cylinder groove.

Picture 7

16 Examine the connection of the thread rod and upper cap for tight fit. If necessary: Apply Loctite 262 to thread and retighten nut.

17 Install the piston tube on the piston tube end acc. to picture 8. Ensure tight fit.

Picture 8 15mm Seal ring (Step 3)Diamond Aircraft Industries GmbH N. A. Otto-Straße 5 A-2700 Wiener Neustadt WI-RSB 42-089 WI-RSB 42NG-017 Revision 1 Page 6 of 8 05-Feb-2013

18 Mount the spacer and the centering pin acc. to picture 9.

Picture 9 19 Apply a coat of Additiv 1U-9891 on the piston tube and the centering pin.
20 Put the cylinder tube over the centering pin on the piston tube.

21 Remove the centering pin with a M12 bolt.

Picture 10

22 Examine the piston end plate: Check the thread excess length of 5 mm between bolt head and restriction washer acc. to picture 11.

Picture 11

23 If adjustment is necessary: Remove the bolt and apply a coat of Loctite 262 to the thread and adjust a thread excess length of 5 mm between bolt head and restriction washer acc. to picture 11. Centering pin

SpacerDiamond Aircraft Industries GmbH N. A. Otto-Straße 5 A-2700 Wiener Neustadt WI-RSB 42-089 WI-RSB 42NG-017 Revision 1 Page 7 of 8 05-Feb-2013

24 Secure the bolt after installation with a prick-punch on the bottom side acc. to picture 12.

Picture 12

25 Install the piston end plate in the cylinder tube with a nut LN 9348 M8. Secure the connection with Loctite 262 acc. to drawing D60-3277-10-00_01.

Picture 13 26 Remove the spacer from piston tube.
27 Install the bottom cap with the bolt, washer and nut.
28 Install the charging valve with a new O-Ring MS 28775-010. Piston end plate

Nut

SpacerDiamond Aircraft Industries GmbH N. A. Otto-Straße 5 A-2700 Wiener Neustadt WI-RSB 42-089 WI-RSB 42NG-017 Revision 1 Page 8 of 8 05-Feb-2013

29 Adjust the direction of the piston tube to the cylinder tube acc. to picture 14.

Note: The charging valve must be aligned with the nut from the bolt holding the bottom cap.

Picture 14 30 Fill and charge the Damper acc. to AMM Section 32-10.
31 Install the Damper to the MLG acc. to AMM Section 32-10.
32 Clean working area and check for foreign objects.

33 Mark damper with “reworked to D60-3277-10-00_1” using a fine permanent marker. Cover the marking with commercial clear coat.

Note Mask around the marking before you apply the clear coat.

Note Choose an inconspicuous location for the marking on the damper (e.g. on the side facing towards the MLG doors).

34 Perform a landing gear extension and retraction test and check clearance between MLG wheel and wheel bay acc. to AMM-TR-MÄM-42-447. 35 Apply anti-corrosion coating on damper connections acc. to AMM Section 12-30.
36 Perform functional check of altered, repaired and new parts.
37 Test all systems in working area for function.

38 Make necessary entries into aircraft logs. Note: Record which MLG damper (LH/RH) has been modified.