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1.75" Piston Kit

  • $53.52
  • or

Koyker OEM Cylinder Part 663306

1 3/4" Cylinder Piston Kit works with certain Koyker front-end loaders. Completely assembled OEM 1 3/4” Cylinder Piston with all seals.

  • Pistons DO NOT work on other brands of loaders or products.
  • Pistons are manufactured specifically to fit Koyker front-end loaders.

NOTE: This product does not qualify for returns. Confirm correct piston and packing kit by comparing pictures, checking owner's manual AND by measuring the inside diameter of the current piston.

The kit includes the following pieces:

Part Number: K663306 (Assembled)

  • (1) 1 3/4" Aluminum Piston
  • (2) 1 3/4" U-Cup Piston Seals
  • (1) 5/8” Rod “O” Ring
  • (1) 5/8" Lock Nut

Related Products:

K663304: 1 3/4" Cylinder Seal Kit
K663305: 1 3/4" Cylinder Gland Kit

Loader Models:

Koyker Loader 120
Koyker Loader 125

Koyker Loader 140
Koyker Loader 145 (Loader may also utilize 2" Cylinder Piston Kit)
Koyker Loader 155 (Loader may also utilize 2" Cylinder Piston Kit)
Koyker Loader 160 (Loader may also utilize 2" Cylinder Piston Kit)
Koyker Loader 165 (Loader may also utilize 2" Cylinder Piston Kit)

Download Koyker Loader Manuals

This product does not qualify for returns. Please make sure this product is the correct size and will work for your equipment before purchasing.

Your equipment may consist of NON-OEM parts and may not coincide with product manuals. If you have questions or concerns, please contact our Koyker Customer Service Team at 1-800-456-1107.


Periodically check all hydraulic system connections to insure a leak-free condition. Also, be certain to maintain proper fluid levels in the tractor hydraulic system as in accordance with the method and frequency recommended in the tractor operator’s manual. Use only hydraulic fluids recommended for your tractor hydraulic system by the manufacturer.

Keep hydraulic system clean. Be certain to maintain recommended oil filter service intervals. All internal surfaces of the hydraulic system on your loader have been factory cleaned, inspected, and plugged with protective caps prior to shipment. Be certain all protective caps are securely in place until hydraulic system assembly is completed.

Care must be taken with your loader cylinders. Nicks, scratches, rust or other shaft damage can cause seal damage resulting in cylinder leakage and poor performance.

Read these service tips before beginning assembly of cylinder gland or piston.

  1. Keep seals clean from the time they are removed from package until they are installed.
  2. Clean the groove or bore into which the seal is to be fitted before installing the seal.
  3. Never touch the seal lip in handling. Always pick up the seal by its outer member.
  4. Inspect each seal lip carefully for nicks, scratches, and dirt at time of installation. If dirty, use a soft, clean cloth and carefully wipe off seal. DO NOT wipe seal with fingers as this only imbeds dirt in the seal.

Never clean rubber related seals with a mineral based solvent! Clean rubber seals in denatured alcohol or non-mineral based solvents only.

Seals can be made more pliable and easier to install, if first heated in hydraulic oil to 160 degrees F. Never use direct heat on any seals.

We try our best to ship orders in the timeliest manner possible. Each product may have a different level of manufacturing demand and timeframe for shipment.

Shipping Rates

We offer calculated shipping rates during the checkout process. USPS, UPS & FedEx services are available if the product ordered qualifies for those options.

Order Processing

Business Days: Monday-Thursday.
Holidays, Fridays, Saturdays and Sundays are not included in processing days.

If you have any questions or concerns about your order's status, please email us at to discuss.

International Orders

Customers are responsible for any brokerage fees incurred on shipping. Sioux Steel Company cannot calculate these fees.


Products on this website do not qualify for returns. We understand this may cause you concern....

We are here to help!

Our customer service team is available Monday-Friday, 8am to 5pm CST to discuss the parts in question PRIOR to placing your order.

Call us toll free at 1-800-557-4689 to talk and confirm your parts needed.

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We distribute products through local dealerships in your area. Prices and product availability may vary between dealerships.

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NOTE: All product specifications are subject to change or improvement without notice. We reserve the right to change product pricing at any time without further notice. Pricing may differ at the time of purchase.

Contact Sioux Steel by emailing or by calling our customer service specialists at 1-800-557-4689 for additional information.

SIOUX STEEL COMPANY FOUNDATION: 2% of the total sales dollars from this website are donated to the Leukemia and Lymphoma Society. Beating cancer is in our blood.

Customer Reviews

Based on 5 reviews

Fast shipping, customer service was wonderful.
Parts fit and worked great.

Thanks for the feedback!

sandra t.
1.75" Piston Kit

Fit and works perfectly. My Koyker loader works like new again.

Thanks for the feedback! Have a great day.

Robin T.
160 koyker bucket cylinder

Worked great arrived in a timely manner

Alan W.
Kit works well .

Parts work well and arrive FAST . Easy to install and back in the saddle again.

Thank you for the wonderful review!

Frank D.
I will order from here again

Received my parts very quickly. I was kept informed throughout the shipping process. Once the parts arrived I was impressed on how well they were put together. I will be buying all of my parts from here in the future.

Thank you Frank for the review!

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Ask a Question
  • I have a Koyker 160 front end loader. I am having a problem with the bucket cylinder or control. When I work the bucket joystick it locks up and kills the motor. Can you help me?

    Greetings! We would suggest giving us a call at 1-800-456-1107 to discuss further. It sounds like a possible scenario is that the joystick control is rusted and it sticks causing the tractor to bog down and the motor to kill. A possible solution would be to take it apart and clean it or maybe just spraying under the boot with wd-40. Thank you for reaching out!


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