This is the most complete kit available for the GM471 landing gear actuator on the Lancair IV/IV-P main gear.  It is similar to Lancair Seal kit HC-471 but includes all the seals, snap rings, and down-lock components required to complete the job.

The kit includes:

• Qty 1 – Actuator Snap Ring
• Qty 1 – Actuator Shaft Wiper
• Qty 1 – Actuator Shaft U-Cup Seal (Polypack)
• Qty 1 – Actuator End Cap O-Ring
• Qty 1 – Actuator End Cap Backup Ring
• Qty 1 – Actuator Piston O-Ring
• Qty 1 – Actuator Piston Bearing
• Qty 1 – Actuator to Down-lock Housing O-Ring
• Qty 1 – Down-lock Piston O-Ring
• Qty 1 – Down-lock Piston Backup Ring
• Qty 14 – Down-lock Belleville Washers
• Qty 1 – Down-lock Snap Ring

This kit services one (1) hydraulic actuator and down-lock assembly.  It does not include the actuator or down-lock mechanism.

Notes:

• Lancair originally shipped units with 12 Belleville washers but later recommended using 14, this slightly improves the retention force on the down-lock pin.  Washers should be installed with the large dias against the piston  and the retainer cap.
• Always install snap rings with the sharp edge facing outside the actuator, this prevents the snap ring from popping out of the groove under load.
• It is recommended to replace the original down-lock retaining cap with 700-0100 (coming March 2026), an upgraded version, this prevents bending of the end cap and loosening of the snap ring in the groove.

This product is designed to fit the Lancair IV, and IV-P models.

Disclaimer:

This seal kit is provided to assist owners and mechanics complete their own repairs to their hydraulic gear actuator. This kit is made of industry standard seals taken directly from the original manufacture’s (Lancair) kits which are no longer in production.  O’Day Design LLC did not design the original actuator, nor size and specify the original seals used in it. As such O’Day Design LLC makes no claim as to the airworthiness of the design or particular actuator being serviced.

O’Day Design LLC assembles these kits as a convenience for owners who would otherwise need to procure these same seals in large qualities to meet minimum order requirements.   It is the installers responsibility to identify any incompatibilities with these seals and the actuator they are working on.

By using this seal kit, the installer, owner, operator, and their representatives understand and assume all risks involved with completing the reseal and subsequently operating the aircraft with the actuator. To the extent permitted by law, they agree to indemnify, defend, and hold harmless O’Day Design LLC from any and all claims, actions, liabilities, suites, injuries, demands, obligations, losses, settlements, judgments, damages, fines, penalties, costs, and expenses, including attorney’s fees and other expenses, (collectively a “Claim”) arising out of, or relating to, the installation or use of this seal kit.

O’Day Design LLC encourages feedback from owners and installers on the content of this kit so that it may be improved for other future installations.

Keyword: GM-471