Landing Gear Cylinder Rebuild

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Having trouble with your nose gear door hydraulic cylinder? So is everyone else. Consider:

Mishler Mechanical Replacement

At Mishler_nose_gear


Landing Gear Actuator's Rebuild Kit Packing's

108-0872 IMG.JPG

Packing's can be ordered from HD distributing over the Phone (877) 838-7325 , Online , or located at (if you would prefer will call):

3236 Irving Blvd.
Dallas, Texas 75247

Cylinder Rebuild

I don't know where you can find a rebuild kit. They seem strangely difficult to locate. I did find some good info in the Lancair community. They use the same pump/cylinder system that Velocities do. According to their experts, the only non-standard part in the pump rebuild kit is the poppet valve, so you only need a rebuild kit if the poppet valve is leaking. Usually, you just need these standard O-rings from McMaster:

013-90, Spool Seal (013N90)
014-90, Check Valve Body seal (014N90)
908-70, Hex Plug Seal
908 Durometer 90

For more info, see Lancair builder Chris Zavatson's site:

Linked below are his diagrams, explanations, and instructions for rebuilding the hydraulic pump and cylinders.


NOTE: Updated version of the page moved here to include pump rebuild info: Retract Pump and Cylinder Rebuild

Main Gear Actuator
2ea.) 212BN70 .859 ID x .139 CS
1ea.) UH-12500562 9/16 x 13/16 x 1/8
1ea.) TP-013 1-1/8 OD x 7/8 ID x 3/16 GW

1ea.) DY-110x5/16 (5/16 SCREW) .301 ID x .603 OD x .054THK

Nose Gear Actuator
2ea.) 212BN70 .859 ID x .139 CS
1ea.) TP-013 1-1/8 OD x 7/8 ID x 3/16 GW

1ea.) DY-110x5/16 (5/16 SCREW) .301 ID x .603 OD x .054THK

1ea.) UH-12500375 3/8 x 5/8 x1/8

Nose Gear *DOOR* Actuator
1ea.) 014BN70 .489 ID X .070 CS
1ea.) UH-12500312 5/16 x 9/16 x 1/8

1ea.) TP-005 5/8 OD x 3/8 ID x 3/16 GW

MIL 5606 uses Nitrile packing's

Pay particular attention to the orientation of the Poly Pak's the open portion faces towards pressure. Looks a little odd buts makes sense if you think about it. The more pressure you put on it causes it to flare out and increase sealing pressure.