A cracked or shattered door glass on your Bobcat T590 can halt operations, compromise visibility, and expose you to weather elements and safety hazards. This comprehensive guide provides a detailed process for replacing the tempered door glass (part #7120401) on Bobcat T590 models from 2014 onward (Tier 4 compliant). With the right tools and parts, this repair typically takes 1-2 hours, saving significant downtime and costs compared to dealership visits.
Safety First: Essential Precautions
Prioritize safety during this repair:
- Wear cut-resistant gloves, safety glasses, and steel-toed boots
- Lock out and tag out the machine (ignition off, key removed, battery disconnected)
- Have a vacuum or broom ready for glass cleanup
- Keep a first-aid kit nearby
- If uncomfortable with any step, consult a certified Bobcat technician
Why Timely Door Glass Replacement Matters
The Bobcat T590's enclosed cab features 6mm thick tempered safety glass with green UV-protective tinting and DOT certification. While designed for durability, impacts from rocks, branches, or equipment collisions can cause damage, especially in:
- Wooded or uneven terrain operations
- Fall foliage clearance projects
- Construction sites with flying debris
- Material handling operations
Consequences of delayed replacement:
- Reduced visibility increasing accident risks
- Water ingress causing cab component rust
- Potential OSHA non-compliance (29 CFR 1926.601)
- Operator exposure to weather elements
Replacing damaged glass promptly—ideally within 60-90 days before winter—maintains productivity and extends machine lifespan. OEM-equivalent parts can save 20-50% over dealer prices without sacrificing quality.
Required Tools and Parts
Essential Tools
- 10mm socket wrench or ratchet – For loosening door hinges (torque to 8 Nm on reinstall)
- Phillips #2 screwdriver – For cab trim screws
- Two large suction cups – Rated for 50+ lbs each; essential for safe glass handling
- Utility razor blade or putty knife – For removing old sealant without frame damage
- Shop towels or microfiber cloths – For cleaning and sealant application
- Silicone sealant – Weatherproof, clear; apply 1/4-inch bead
- Penetrating oil – For stuck hinges
- Torque wrench – Prevents over-tightening and frame distortion
- Vacuum or broom – For glass shard cleanup
Required Parts
- Bobcat T590 tempered door glass (#7120401)
- Door seal kit (#7281063)
- Optional: Door plug (#7258389) – If your model has additional access points
- Optional: Polycarbonate upgrade – For high-impact environments
Estimated Cost: $200-300 for parts versus $500+ at dealership with labor
Pre-Repair Inspection
Before beginning:
- Park the T590 on flat, stable ground
- Lower all attachments completely
- Inspect glass for cracks, chips, or fogging (seal failure indicator)
- Check door frame for bends or rust (sand and prime minor rust)
- Confirm model year (2014+) via serial plate near cab
- Consider polycarbonate upgrade for forestry applications (offers better shatter resistance but may scratch more easily)
Step-by-Step Replacement Process
Step 1: Prepare the Work Area
- Position loader in well-lit, spacious area with room for full door opening
- Lower bucket to ground
- Shut off engine and remove key
- Engage lockout/tagout device
- Disconnect battery negative terminal
- Lay protective mats or tarps to catch glass fragments
- Put on all PPE
Step 2: Remove the Damaged Door Glass
- Open cab door and support it with prop or assistant
- Using 10mm wrench, loosen four hinge bolts (two per hinge) gradually—start with bottom ones
- Attach suction cups to glass center with firm pressure
- Score old sealant around glass perimeter with razor blade, working in sections
- Gently pry glass from frame, tilting outward
- If glass sticks, apply penetrating oil to edges and wait 5-10 minutes
- Lift glass out using suction cups and place on padded surface for disposal
- Vacuum all shards from frame
Pro Tip: Patience prevents frame cracking—rushing this step is the most common mistake.
Step 3: Clean and Prep the Door Frame
- Wipe frame groove with shop towels and isopropyl alcohol to remove old sealant, dirt, and rust
- Inspect hinges for wear and lubricate with grease if needed
- Dry area completely for proper sealant adhesion
Step 4: Install the New Door Glass
- Unbox new glass (#7120401) and verify dimensions (790mm × 1060mm) and hole alignments
- Apply continuous 1/4-inch bead of silicone sealant into frame groove without gaps
- Using suction cups, position new glass into frame, aligning with hinges
- Press evenly into place
- Reinstall hinge bolts hand-tight, then torque to 8 Nm in cross pattern for even pressure
- Wipe away excess sealant immediately with damp cloth
Step 5: Attach and Secure the Seal Kit
- Fit new door seal (#7281063) around glass edge, starting at bottom
- Work upward, pressing seal firmly into place
- Ensure no bubbles or loose sections—use roller tool if available
- Check door alignment by closing gently
- Adjust hinges if binding or gaps appear
Step 6: Final Testing and Cleanup
- Reconnect battery
- Start engine
- Test door operation: open/close multiple times, checking for smooth movement and no rattles
- Simulate rain with hose to verify seal against leaks
- Clean new glass with non-ammonia cleaner for streak-free visibility
- Dispose of old glass responsibly (recycle if possible)
- Log repair in maintenance records
Troubleshooting Common Issues
Stuck Hinges
- Apply penetrating oil and wait 10-15 minutes
- Use gentle heat from hairdryer if oil fails
- Never force with excessive pressure
Seal Mismatches
- Always order M-series specific kits
- Verify part numbers match your model year
- Check seal orientation before installation
Poor Glass Fit
- Verify specifications: 6mm thick, 790×1060mm
- Check for bent hinges or frame damage
- Use washers as shims if minor adjustment needed
- Consult professional if significant misalignment occurs
Vibration Issues
- Add anti-vibration pads under hinges for high-vibration job sites
- Recheck torque specifications
- Ensure even pressure distribution across all mounting points
Tempered Glass vs. Polycarbonate: Which to Choose?
Tempered Glass (#7120401) – Standard Option
Benefits:
- Superior optical clarity
- Scratch-resistant surface
- Cost-effective ($200-250)
- DOT-certified safety glass
Best for: General construction, grading, material handling
Polycarbonate – Premium Option
Benefits:
- 250× impact resistance over glass
- Virtually unbreakable
- Lighter weight
Drawbacks:
- Scratches more easily
- May yellow over time
- 20% higher cost
Best for: Forestry operations, high-debris environments, frequent impact zones
Maintenance Tips for Extended Glass Life
- Monthly inspections: Check for chips, cracks, or seal degradation
- Clean regularly: Use non-ammonia glass cleaner to prevent buildup
- Seasonal prep: Inspect before fall foliage season and winter
- Proper operation: Avoid slamming door or operating with damaged glass
- Seal maintenance: Check weatherstripping quarterly for wear
Frequently Asked Questions
How long does Bobcat T590 door glass replacement take?
The process typically takes 1-2 hours for operators with proper tools. First-time DIYers may need an additional 30-60 minutes. Having parts like #7120401 and #7281063 ready before starting prevents delays.
When should I replace my Bobcat T590 door glass immediately?
Replace immediately if you notice:
- Cracks or chips larger than a quarter
- Fogging between layers (seal failure)
- Reduced visibility from extensive scratches
- Any compromise that could violate OSHA standards
- Increased cabin noise or drafts
Address issues before winter to prevent cab interior damage.
Can I reuse the old seal kit during replacement?
No. Reusing old seals risks leaks and poor fit, leading to water damage or dust ingress. Always use a new seal kit (#7281063) for reliable weather-tight sealing. At $20-30, it's an inexpensive insurance policy for long-term protection.
What torque specifications should I follow for hinge bolts?
Tighten to 8 Nm using a torque wrench in a cross pattern. Over-tightening warps the frame, causing alignment issues or stress cracks. Under-tightening leads to vibrations and premature wear. This specification comes from Bobcat's official service manual.
How does seasonal maintenance affect door glass longevity?
Fall (October-November): Increased foliage and debris heighten breakage risks. Inspect before harvest or landscaping peaks.
Winter: Ensure seals prevent frost buildup and cold air infiltration. Check weatherstripping for cracks.
Spring/Summer: Clean glass frequently to remove dust and pollen buildup.
What if the new glass doesn't fit perfectly?
Mismatches typically stem from:
- Non-OEM parts with incorrect specifications
- Frame damage or bent hinges
- Wrong model year parts
Solutions:
- Verify specs: 6mm thick, 790×1060mm
- Check frame for damage before installation
- Use washers as shims for minor adjustments
- Consult certified technician for significant issues
Is polycarbonate worth the extra cost?
Polycarbonate is worth considering if your T590 operates in:
- Dense forestry environments
- High-debris construction sites
- Demolition operations
- Areas with frequent flying rock or branch impacts
For standard grading, excavation, and material handling, tempered glass provides excellent protection at lower cost.
Conclusion
Replacing your Bobcat T590 door glass is a straightforward repair that protects your investment and ensures operator safety. By following this guide and using quality OEM-equivalent parts, you can complete the job in 1-2 hours while saving $300-400 compared to dealership service. Regular inspections and proper maintenance extend glass life and prevent costly emergency replacements.
Ready to get started? Order your Bobcat T590 door glass (#7120401) and seal (#7281063) today to maintain peak operational efficiency through all seasons.