Multiquip 21770 Eaton Motor Key

The Multiquip 21770 is a genuine OEM Eaton Motor Key designed for HTX44K5, HTX44Y4, HTX44Y5, and HTX44K4 hydrostatic ride-on power trowels. As a direct Multiquip OEM part, it meets the exact material and dimensional standards required to maintain proper hydraulic motor shaft engagement on these machines. This key is a direct replacement for the original component, with no modifications needed to the motor or shaft assembly. If you are servicing an HTX44 series trowel, verifying part number 21770 ensures you receive the correct key for your application.

Key Features

• Genuine OEM Construction — Manufactured to Multiquip's exact material hardness and dimensional tolerances required for hydraulic motor shaft keying, ensuring proper torque transfer without slippage.
• Direct-Fit Replacement — Seats directly into the Eaton motor keyway on HTX44 series trowels, aligning with the original shaft slot for a clean, tool-assisted installation.
• HTX44 Series Compatibility — Confirmed fitment for HTX44K5, HTX44Y4, HTX44Y5, and HTX44K4 hydrostatic ride-on power trowels.
• Maintains Hydraulic Drive Integrity — A correctly seated motor key locks the drive shaft and motor hub in phase, preserving consistent blade speed and hydrostatic drive response during finishing operations.
• Critical Drivetrain Component — A worn or missing key allows shaft-to-hub slippage, causing erratic blade rotation, accelerated keyway wear, and potential hydraulic motor damage if left unaddressed.

The Eaton Motor Key is a small but critical drivetrain component that locks the hydraulic motor's output shaft to the driven hub or sprocket, ensuring rotational force is transmitted without slippage. On hydrostatic ride-on trowels like the HTX44 series, the Eaton hydraulic motor controls blade rotation, so a correctly fitted key is essential for consistent finishing speed and operator control. When this key shears, rounds out, or goes missing, the shaft spins freely inside the hub, causing loss of blade drive and rapid wear to the surrounding keyway that can make the repair significantly more involved.

Part Details

Compatibility & Fitment

Verify Before You Order

Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.

Why Buy From DHS Equipment

Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.

Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.