Kubota U35-4 Mini Excavator – Parts, Specs & Serial Number Guide

The Kubota U35-4 is a powerful, maneuverable 3.5-ton class mini excavator with a zero-tail swing design that allows safe and efficient operation in tight spaces. Known for its balanced performance and operator-friendly features, the U35-4 is popular among utility contractors, landscapers, and municipal workers. With a deluxe cab, precision controls, and flexible auxiliary hydraulics, the U35-4 is designed for comfort and productivity on any job site.

Key Specifications:

Engine:

• Model: Kubota D1703-M-DI-E4B

• Type: 3-cylinder, liquid-cooled, diesel engine (Tier 4 Final)

• Displacement: 100.5 cu in (1.647 L)

• Gross Power: 23.9 hp (17.8 kW) @ 2,200 rpm

Transmission & Travel:

• Travel Speed: Low: 1.8 mph (2.9 km/h), High: 3.1 mph (5.0 km/h)

• Drive Motors: Hydraulic piston motors with auto-downshift

Hydraulic System:

• Pump Capacity: 38.4 + 38.4 + 23.5 l/min (triple pump system)

• Auxiliary Flow: 15.8 gpm (60 L/min)

• Max Operating Pressure: 2,611 psi (180 bar)

• Hydraulic Controls: Proportional thumb control, adjustable auxiliary flow

Dimensions:

• Operating Weight: 8,129 lbs (3,688 kg)

• Max Digging Depth: 10 ft 6 in (3.2 m)

• Max Reach at Ground Level: 17 ft 1 in (5.2 m)

• Tail Swing Radius: Zero-tail swing

Performance:

• Bucket Breakout Force: 9,535 lbf (42.4 kN)

• Arm Digging Force: 4,250 lbf (18.9 kN)

Maintenance & Common Parts:

Routine Maintenance Needs:

• Change engine oil and filter every 250 hours

• Replace hydraulic oil and filters every 500 hours

• Inspect and grease boom, arm, and bucket pins every 10 hours

• Check and adjust rubber track tension weekly

Frequently Replaced Parts:

• U35-4 Hydraulic Cylinder Seal Kits

• Final Drive Motors

• Rubber Tracks & Rollers

• Engine Filters (Air, Fuel, Oil)

• Control Valves & Thumb Kits

Common Issues & Quick Fixes:

• Auxiliary hydraulics not responding: Check thumb control switch and fuse panel. Replace faulty valve solenoids or switches.

• Track de-tracking on turns: Usually caused by worn sprockets or loose tension—tighten or replace with OEM-fit tracks and idlers.

• Hydraulic drift or slow lift: Indicates leaking cylinder seals—install new hydraulic cylinder kits.

Pro Tips:

• Make use of the adjustable auxiliary hydraulic flow to match flow rate to different attachments like thumbs or augers.

• Clean radiator and oil cooler screens weekly to avoid overheating.

• Check blade wear and replace cutting edge if it becomes rounded.

Serial Number Location:

• Found on a metal plate on the right front of the machine's frame (near the blade arm) and inside the operator’s compartment under the seat.

• Use your serial number when ordering exact-fit Kubota U35-4 parts.