Comprehensive Guide: How to Replace & Maintain Kubota U17 Mini Excavator Tracks

Mastering rubber track replacement and undercarriage maintenance on the Kubota U17 mini excavator is critical for maximizing machinery uptime, reducing component wear, and ensuring job site safety. This expert technical guide covers operational risks, early wear symptoms, pre-job setup, step-by-step track installation, undercarriage inspection parameters, and long-term track care.

Quick Reference Technical Specifications

Machine Model	Track Width	Recommended Track Sag (Tension)	Torque Specification	Idler Axial Play Limit	Minimum Sprocket Tooth Height
Kubota U17	230 mm (9 in)	20 – 25 mm (Thumb's width)	300 – 400 ft-lbs	5.0 mm	70% of OEM spec

Why Do Kubota U17 Excavators Lose Tracks?

Mini excavators frequently experience track derailment or tension loss due to aggressive job site conditions, maneuvering errors, and improper maintenance.

• Demanding Terrains: Frequent sharp counter-rotations on hard concrete, gravel, or rocky ground exert massive lateral stress on track guide lugs, forcing the rubber track off the idler.

• Debris Accumulation: Packed mud, rocks, and job site debris wedge inside the track frame, pushing the rubber track away from the bottom rollers and drive sprockets.

• Grease Cylinder Leakage: Worn seals on the hydraulic tensioning cylinder valve allow grease to escape, causing the front idler to retract and slacken the track during heavy digging operations.

• Operational Technique: Driving across steep slopes at high speeds or turning sharply with a fully loaded bucket increases the risk of throwing a track.

Symptoms of Loose, Worn, or Damaged Tracks

Routine inspection of undercarriage components helps operators identify track issues before catastrophic failure occurs on the job.

• Sprocket Skipping & Slippage: Loose or stretched tracks cause drive sprocket teeth to jump or slip over internal steel drive lugs, producing audible clunking sounds during travel.

• Visible Internal Steel Cording: Deep rubber gouges that expose internal continuous steel cords allow moisture to enter, leading to rapid steel corrosion and sudden track snapping under load.

• Rubber Dry-Rot & Stress Cracking: Long-term UV exposure, harsh chemicals, and aggressive ground contact create micro-cracks along the outer tread and inner guide rails.

• Guide Rail & Roller Deterioration: Flange wear on track rollers and front idlers leads to persistent track misalignment and repeated track derailment.

Required Tools & Safety Equipment

Having the correct, high-grade tools prepared before starting track replacement speeds up the process and prevents component damage.

Equipment & Tool Specifications

Tool / Equipment	Application	Specification / Technical Requirement
Hydraulic Lift / Boom & Blade	Raising the excavator track frame	Machine hydraulics + rated jack stands (3-ton min)
Socket Wrench Set	Removing access plate & grease valve	17 mm or 22 mm deep sockets
Torque Wrench	Fastening undercarriage hardware	300 – 400 ft-lbs capacity
Heat-Treated Heavy Pry Bar	Levering rubber tracks off idler/sprocket	48+ inches alloy steel pry bar
High-Pressure Grease Gun	Re-tensioning the hydraulic cylinder	Standard grease gun with lithium grease
Stabilization Blocks	Structural machine support	Heavy-duty hardwood timber or rated jack stands

Safety Precautions

CRITICAL SAFETY WARNING: Never work under or around an elevated excavator supported only by its hydraulic system. Hydraulic lines can lose pressure unexpectedly. Always insert rated jack stands or solid wooden timber blocks beneath the frame prior to track removal.

• Hydraulic Stabilization: Keep the engine running at low idle to maintain hydraulic pressure when raising the chassis using the boom and dozer blade.

• Control Lever Lockout: Engage the hydraulic lock lever inside the cab to disable pilot controls before approaching the track frame.

• Personal Protective Equipment (PPE): Operators must wear steel-toe boots, heavy-duty work gloves, and protective eyewear to protect against high-pressure grease discharge.

Step-by-Step Instructions: How to Replace Kubota U17 Tracks

Step 1: Park, Elevate, and Secure the Excavator

• Park the Kubota U17 on flat, hard, and level ground.

• Lower the rear dozer blade into the ground to raise the rear end. Push the front boom and bucket down against the ground at the front end to lift the track side approximately 2 to 4 inches off the surface.

• Engage the hydraulic safety lock lever inside the cab.

• Position heavy-duty safety jack stands or solid timber blocks under the frame to ensure mechanical stability.

Step 2: Release Track Tension

• Locate the small access cover plate on the side of the track frame near the front idler wheel.

• Remove the cover plate and use a 17 mm or 22 mm socket wrench to carefully loosen the grease adjuster valve counterclockwise.

• Do not fully unscrew the valve. Allow grease to discharge into a catch rag. Apply foot pressure to the center of the track to force the front idler back into the track frame and release track pressure.

Step 3: Remove the Old Rubber Track

• Insert a heavy-duty pry bar between the rubber track and the top edge of the front idler wheel.

• Slowly operate the track drive in reverse while levering the track outward to walk the rubber track off the idler pulley.

• Slide the track off the rear drive sprocket teeth and remove the track completely from the undercarriage frame.

Step 4: Inspect Undercarriage Components

Before installing the replacement track, inspect key undercarriage wear components using calipers and dial indicators:

• Drive Sprockets: Check for pointed or hooked tooth wear. Replace sprockets if tooth height falls below 70% of OEM specifications.

• Front Idlers: Measure axial play using a dial indicator. Axial play exceeding 5.0 mm indicates internal bearing failure and requires idler replacement.

• Track Rollers: Inspect roller flanges for flat spots, cracking, or oil seal leakage.

Step 5: Install the New Rubber Track

• Clean packed dirt, rocks, and debris from the undercarriage rails, rollers, and sprocket teeth.

• Pro Tip: Place the new rubber track in the sun prior to installation. Warm rubber is significantly more pliable and easier to maneuver over the idler.

• Position the new track over the rear drive sprocket teeth first. Ensure the V-shaped tread pattern points forward in the direction of forward travel.

• Leverage the front edge of the rubber track over the front idler wheel using a pry bar while gently operating the track drive forward until the track seats properly into all roller grooves.

Step 6: Adjust and Test Track Tension

• Clean the grease valve threads, re-insert the valve into the housing, and tighten it securely.

• Attach a grease gun to the grease zerk fitting and pump fresh lithium grease into the cylinder until the front idler extends forward.

• Measure the track sag beneath the middle track roller flange. Stop pumping when the clearance reaches 20–25 mm (approximately a thumb's width).

• Lower the machine to the ground, track the machine forward and backward slowly for two minutes to equalize tension and clear air pockets, and re-check the sag measurement.

Frequently Asked Questions

How often should Kubota U17 rubber tracks be replaced?

Rubber tracks generally last between 1,800 and 2,200 operating hours. However, lifespan varies depending on soil abrasion, operator habit, and tension maintenance. Replace tracks immediately if lug height drops past 30% of original height or if internal steel cords are visible.

Can I install Kubota U17 tracks without specialized track press tools?

Yes. Standard replacement can be performed using basic shop tools such as socket sets, heavy-duty pry bars, and a high-pressure grease gun. Avoid using hammers directly on track links or pins, as sudden impacts can create micro-fractures in structural steel.

What are the key maintenance steps for extending track life?

Regularly check track tension, clean packed mud from the undercarriage after every shift, avoid sharp high-speed pivots on concrete, and replace worn sprockets promptly to prevent accelerated wear on new rubber track lugs.

This article is part of the rubber tracks guide, which covers how the size code works, tread patterns, compounds and buying a set in Canada.