Hynautic KS-06 Seal Kit for K21-29 Cylinders Post 1983

Hynautic KS-06 - Seal Kit for K-21 to K-29 Cylinders (Post 1983)

KS-06 is the genuine Hynautic cylinder seal kit for resealing K-21 through K-29 steering cylinders manufactured after August 1983 (post-1983). Use this kit to refresh internal sealing surfaces to help address bypassing and leakage caused by worn seals.

Compatibility

• Fits: Hynautic K-21, K-22, K-25, K-26, K-27, K-28, K-29 cylinders post-1983 (after August 1983)
• Does not fit: K-21 to K-29 cylinders pre-1983 - use KS-04 instead
• How to confirm: Check the cylinder’s stamped model on the end cap or barrel and note approximate build date. If unsure, contact Tech Support with photos of the end cap and rod end.

What’s Included

• Seal and O-ring set for one K-21 to K-29 cylinder (post-1983)
• Rod wiper(s) and backup rings as applicable
• Retaining wire or clip as applicable

Note: Contents can vary slightly by cylinder revision. Reuse of hard parts is expected unless damaged.

Related Hynautic Cylinder Seal Kits

Install Overview - Resealing a Hynautic Cylinder

This is a high-level overview to help you plan the job. Follow the Hynautic service manual for exact steps and specs.

1. Prep - Clean the exterior, secure steering, and mark current hardware locations. Protect the rod from scratches.
2. Disassemble - Depressurize the system. Remove retaining wire(s) and end cap per the manual. Withdraw rod and piston assembly.
3. Inspect - Check the rod surface for nicks and the bore for scoring. Replace damaged hard parts before reseal.
4. Reseal - Replace O-rings, backups, and wipers from KS-06. Lightly lubricate seals with compatible hydraulic fluid.
5. Reassemble - Install rod assembly, seat end cap, and re-fit retaining wire(s). Verify smooth travel by hand.
6. Bleed and test - Refill, bleed air, and verify full stroke without binding or leaks. Sea trial under safe conditions.

Tip: If the rod is pitted or the bore is scored, a reseal may not hold. Consider our Hynautic cylinder rebuild service.

Downloads and Resources

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