Throttle Stepper Motor for Kobelco SK200-6 / Hitachi EX200-5 - Replaces YN20S00002F1, 4360509

Fix Your "Stuck at Idle" Excavator

Your throttle dial works. The engine starts. But it won't rev up. You're stuck at idle, the machine can't dig, and every hour on the clock is money burning. The dealer wants $600 and a 3-week wait. You need this motor now.

This is the direct replacement Throttle Stepper Motor for Kobelco Mark VI and Hitachi EX-5 / ZX Series excavators. It's the identical motor specification used by the OEM — same gear ratio, same torque, same connector. Swap it in and you're back to full throttle.

The Problem

Older excavators from 2000–2010 use mechanical engines with electronic throttle control. A small stepper motor pulls the throttle cable based on the dial position in the cab. When this motor fails, the symptoms are unmistakable:

• Stuck at idle: Engine starts but won't rev above low idle regardless of throttle dial position
• Erratic RPM: Engine RPM hunts up and down on its own, never stabilizing
• Grinding/clicking noise from the throttle motor area (stripped internal gears)
• Throttle dial unresponsive: No change in engine speed when adjusting the dial
• "E-throttle" or "Step Motor" fault code on the monitor display

Why It Fails

The stepper motor has small internal plastic gears that strip over time. Once the gears strip, the motor spins but can't pull the throttle cable. The motor can also burn out electrically from voltage spikes or water intrusion at the connector.

The Solution

This is a direct drop-in replacement. Remove the 2 mounting bolts, disconnect the 7-pin round plug, and swap in the new motor. The entire job takes 30 minutes with basic hand tools. No programming required.

Technical Specifications

• OEM Part Number — Kobelco: YN20S00002F1
• OEM Part Number — Hitachi: 4360509, 4614911
• Type: High Speed Stepper Motor
• Connector: 7-Pin Round Plug (verify your plug before ordering)
• Cable: Standard mechanical cable with loop end
• Condition: Brand New

Compatible Equipment

Kobelco (Dynamic Acera Series)

• Kobelco SK200-6 / SK200-6E Excavator
• Kobelco SK210-6 / SK210-6E Excavator
• Kobelco SK230-6 / SK230-6E Excavator
• Kobelco SK250-6 / SK250-6E Excavator
• Kobelco SK290-6 Excavator
• Kobelco SK330-6 / SK330-6E Excavator

Hitachi

• Hitachi EX200-5 Excavator
• Hitachi EX210-5 Excavator
• Hitachi EX230-5 Excavator
• Hitachi ZX200 Excavator
• Hitachi ZX210 Excavator
• Hitachi ZX230 Excavator
• Hitachi ZX240 Excavator

This motor fits all Kobelco Mark VI and Hitachi EX-5 / early ZX series machines that use the YN20S00002F1 / 4360509 throttle stepper motor. Check your parts manual to confirm fitment.

Why Buy From Trenchwell?

• Save $300+ vs Dealer: OEM dealers charge $450–$650 for this motor. We sell it for $189.
• Heavy-Duty Build: Metal gear construction and reinforced winding for long service life in harsh conditions.
• Ships Fast: Lightweight motor, ships quick. Your machine could be back to work in days, not weeks.
• Stop Losing Money: A non-digging excavator costs you $500–$1,000 per day in lost revenue. Fix it for $189.

Installation Tips

1. Disconnect the battery before removing the old motor.
2. Remove the 2 mounting bolts and disconnect the 7-pin connector.
3. Detach the throttle cable loop from the motor arm.
4. Install the new motor and reconnect everything.
5. Critical — Learning Procedure: Turn the key to ON (don't start the engine), wait 5 seconds, turn OFF. Repeat this 3 times. This allows the ECU to calibrate the new motor's position range.
6. Start the engine and verify throttle response across the full dial range.