Hynautic KS-12 Seal Kit for K2(B) Cylinders

Hynautic KS-12 - Seal Kit for K-2(B) Cylinder

KS-12 is a genuine Hynautic cylinder seal kit used to reseal the K-2(B) inboard steering cylinder. Use this kit when servicing a cylinder with seepage at the rod gland, moisture intrusion, or suspected internal bypass due to worn seals - provided the rod and bore are in good condition.

Compatibility

• Fits: Hynautic K-2(B) steering cylinders
• Does not fit: Standard K-2 (non-B) cylinders - see KS-03 (legacy/discontinued) for K-2 and H-100 applications
• How to confirm: Check the cylinder’s stamped model on the end cap or barrel. If unsure, contact Tech Support with photos.
• Qty needed: One (1) kit reseals one (1) cylinder

What’s Included

• Seal and O-ring set for one K-2(B) cylinder
• 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.

Installation Tips

• Protect the rod: Do not clamp on or scratch the polished rod surface - even small nicks can cause immediate leaks.
• Keep it clean: Dirt around the gland can cut new seals during assembly. Clean the exterior before disassembly.
• Inspect before reseal: Rod pitting or bore scoring can prevent a lasting repair. If wear is present, consider rebuilding.
• Lubricate seals: Use a light film of compatible steering/hydraulic fluid during assembly - do not install seals dry.
• Bleed after service: Any air introduced must be fully bled to restore consistent steering feel.

Maintenance Guidelines

• Inspect the rod and gland area periodically for fluid film, salt buildup, and corrosion.
• Keep bilges as dry as practical and rinse salt deposits around the cylinder when accessible.
• If steering feel changes (drift, pull, or frequent correction), verify fluid level and bleed the system before condemning components.

FAQs

Will KS-12 fix internal bypass?
Sometimes. If bypass is caused by worn internal seals and the rod/bore are in good condition, resealing can restore performance. If the bore is scored or corrosion is present, a rebuild is typically the better long-term fix.

How do I confirm I have a K-2(B) cylinder?
Look for the cylinder model stamped on the barrel or end cap. If it is unreadable, send photos to our Tech Support Page.

Do I need one kit per cylinder?
Yes - one KS-12 kit is intended to reseal one cylinder.

Related Hynautic Cylinder Seal Kits

Downloads and Resources

Questions?

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