Diamond Aircraft Industries GmbH 

N. A. Otto-Straße 5 

A-2700 Wiener Neustadt 

WI-MSB 42-095

WI-MSB 42NG-026

Revision 1

Page 1 of 4

05-Feb-2013

WORK INSTRUCTION 

WI-MSB 42-095 / WI-MSB 42NG-026 

I GENERAL INFORMATION

I.1 Subject

Replacement of nut in MLG damper 

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) All work must be done by a certified aircraft service station or a certified aircraft 

maintenance mechanic. 

b) All work, in particular that which is not especially described in this work instruction, 

must be done 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) 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

Spacer X00-W027-00-00.02 Rev."-" 

II.3 Material

Quantity Part No. Description 

2 ORAR00227-N7083 O-Ring 

2 MS 28775-010 O-Ring 

2 LN 9348-08 Hexagon nut 

2 LN 9348-06 Hexagon nut 

100ml 1U-9891 or equivalent Additiv 1U-9891 Caterpillar Inc.

Materials including special tools are available from Diamond Aircraft Industries. 
Diamond Aircraft Industries GmbH 

N. A. Otto-Straße 5 

A-2700 Wiener Neustadt 

WI-MSB 42-095

WI-MSB 42NG-026

Revision 1

Page 2 of 4

05-Feb-2013

II.4 Consumables 

Quantity Part No. Description 

Approx. 2 l 3627020L Aero Shell Fluid 41 

a. r. Royoco 81MS Grease Royoco 81MS 

a. r. 135376 Loctite 262 

Consumables may be procured locally or from Diamond Aircraft Industries 

III INSTRUCTIONS

1 Make sure AMM-TR-MÄM-42-368 and AMM-TR-MÄM-42-447 are incorporated into 

the AMM. 

2 Remove the LH 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: Always wear safety glasses. The damper is gas loaded. 

 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. 

Picture 1 

4 Remove the charging valve from damper and install spacer. 

5 

Remove the bottom cap: 

 Remove the bolt holding the bottom cap. 

 Pull the bottom cap from the damper assembly. 

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. 
Diamond Aircraft Industries GmbH 

N. A. Otto-Straße 5 

A-2700 Wiener Neustadt 

WI-MSB 42-095

WI-MSB 42NG-026

Revision 1

Page 3 of 4

05-Feb-2013

6 Remove the nut on the piston end plate. 

7 

Install nut LN 9348-08 on the piston end plate. Secure the connection with Loctite 

262 i.a.w. drawing D60-3277-10-00_01. 

Picture 2 

8 Allow Loctite to cure before filling (Minimum cure time 12 hours). 

9 Install the bottom cap with the bolt, washer and nut. 

10 Remove the spacer from piston tube. 

11 Install the charging valve with a new O-Ring MS 28775-010. 

12 

Adjust the direction of the piston tube to the cylinder tube acc. to picture 3. 

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

bottom cap. 

Picture 3 

13 Fill and charge the Damper acc. to AMM Section 32-10. 

14 Install the Damper to the MLG acc. to AMM Section 32-10. 

Piston end plate 

Nut 

Spacer 
Diamond Aircraft Industries GmbH 

N. A. Otto-Straße 5 

A-2700 Wiener Neustadt 

WI-MSB 42-095

WI-MSB 42NG-026

Revision 1

Page 4 of 4

05-Feb-2013

15 

Mark damper with “modified i.a.w. MSB 42-095 / MSB 42NG-026” 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). 

16 Perform steps 2 through 15 on the RH MLG damper. 

17 Clean working area and check for foreign objects. 

18 Do a landing gear extension and retraction test and check clearance between MLG 

wheel and wheel bay i.a.w. AMM Section 32-10. 

19 Apply anti-corrosion coating on damper connections i.a.w. AMM Section 12-30. 

20 Perform functional check of altered, repaired and new parts. 

21 Test all systems in working area for function. 

22 Make necessary entries into aircraft logs.