Overhaul Kit Cord Cylinder Lely A3/A4 BLACK

Overhaul Kit for Cord Cylinder BLACK (New Type)

The Overhaul Kit for Cord Cylinder BLACK is a critical maintenance set designed to restore the pneumatic performance and sealing integrity of the teat cup retraction system on Lely Astronaut A3 and A4 robots. This kit is specifically for the "New" style black cylinders manufactured up to and including March 2017.

Product Specifications

Why Overhaul the Cord Cylinder?

The cord cylinder is responsible for the rapid and smooth retraction of the teat cups. Over millions of cycles, the internal seals can wear down due to friction and exposure to compressed air moisture.

Symptoms of a failing cylinder include:

• Slow Retraction: Teat cups "drift" back slowly rather than snapping back to the arm.
• Incomplete Retraction: The cup hangs down, risking being stepped on by the cow.
• Audible Leaks: Hissing sounds coming from the cylinder end-caps when the vacuum is engaged or disengaged.
• Jerky Movement: The piston "stutters" due to high friction from degraded seals.

Installation Insight

• Check the Sticker: Before ordering, verify the manufacturing date on the cylinder body. If your cylinder was made after March 2017, it may require a different seal profile.
• Cleanliness is Critical: When opening the cylinder, ensure no grit or barn dust enters the bore. Even a tiny scratch on the inner cylinder wall can cause a permanent air leak that a new seal cannot fix.
• Lubrication: Use only the specialized pneumatic grease provided in the kit. Petroleum-based lubricants can cause the rubber seals to swell and fail prematurely.

Maintenance Schedule

It is generally recommended to overhaul or replace cord cylinder seals every 2 years or as part of a major preventive maintenance (PM) cycle to avoid emergency downtime during milking.