The Bobcat T870 compact track loader is a powerhouse, renowned for its impressive lifting capacity, pushing power, and versatility on construction sites, farms, and landscaping projects. But even the toughest machines can encounter problems. This guide is designed to help you diagnose and troubleshoot common issues with your Bobcat T870, keeping you operational and minimizing downtime.
Understanding Your T870: A Quick Overview
Before diving into specific problems, it's helpful to understand the core systems of your T870. These include:
- Engine: The heart of the machine, providing the power for all hydraulic functions and movement.
- Hydraulic System: Powers the loader arms, bucket, auxiliary attachments, and drive motors.
- Drive System: Consists of hydraulic motors and tracks that propel the machine.
- Electrical System: Controls starting, lighting, instrumentation, and electronic control modules (ECMs).
- Cooling System: Regulates engine temperature, preventing overheating.
Knowing how these systems interact will make troubleshooting much easier.
Engine Troubles: When Your T870 Won't Start or Runs Rough
Engine problems are a common source of frustration. Here's a breakdown of potential causes and solutions:
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Won't Start At All?
- Dead Battery: Check the battery voltage with a multimeter. A reading below 12.4 volts indicates a low charge. Try jump-starting the machine or charging the battery. Consider replacing the battery if it's old or consistently failing to hold a charge.
- Faulty Starter: Listen for a clicking sound when you turn the key. If you hear a click but the engine doesn't crank, the starter motor might be bad. Have it tested or replaced.
- Fuel Problems:
- Empty Fuel Tank: Sounds obvious, but double-check!
- Clogged Fuel Filter: Replace the fuel filter regularly as part of your maintenance schedule. A clogged filter restricts fuel flow to the engine.
- Air in Fuel Lines: Bleed the fuel system to remove any air. Consult your operator's manual for the proper procedure.
- Faulty Fuel Pump: A failing fuel pump can't deliver enough fuel to the engine. Have it tested and replaced if necessary.
- Safety Interlocks: Bobcat machines have safety interlocks that prevent starting if certain conditions aren't met (e.g., seat belt unbuckled, parking brake not engaged). Ensure all safety interlocks are properly engaged.
- Ignition Switch: A faulty ignition switch can prevent the engine from starting. Test the switch with a multimeter.
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Engine Starts But Runs Rough?
- Dirty Air Filter: A clogged air filter restricts airflow to the engine, causing it to run poorly. Clean or replace the air filter.
- Faulty Injectors: Dirty or damaged fuel injectors can disrupt the fuel-air mixture. Have them cleaned or replaced.
- Low Compression: Low compression in one or more cylinders can cause rough running. This is a serious problem that requires professional diagnosis and repair.
- Vacuum Leaks: Vacuum leaks can disrupt the engine's air-fuel mixture. Inspect vacuum hoses for cracks or damage.
- Faulty Sensors: Modern engines rely on sensors to monitor various parameters. A faulty sensor can send incorrect information to the engine control module (ECM), causing performance problems. Common culprits include the oxygen sensor, mass airflow sensor, and crankshaft position sensor.
Hydraulic System Issues: Loss of Power and Leaks
The hydraulic system is crucial for operating the loader arms, bucket, and attachments. Problems here can significantly impact productivity.
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Loss of Hydraulic Power?
- Low Hydraulic Fluid Level: Check the hydraulic fluid level and add fluid as needed. Use the correct type of hydraulic fluid specified in your operator's manual.
- Clogged Hydraulic Filter: Replace the hydraulic filter regularly. A clogged filter restricts hydraulic fluid flow.
- Faulty Hydraulic Pump: A failing hydraulic pump can't generate enough pressure. Have it tested and replaced if necessary.
- Sticking or Leaking Valves: Hydraulic valves control the flow of fluid to different components. Sticking or leaking valves can cause a loss of power or erratic operation.
- Relief Valve Problems: Relief valves protect the hydraulic system from overpressure. A faulty relief valve can open prematurely, causing a loss of power.
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Hydraulic Leaks?
- Loose Fittings: Check all hydraulic fittings for tightness. Tighten any loose fittings.
- Damaged Hoses: Inspect hydraulic hoses for cracks, cuts, or abrasions. Replace any damaged hoses.
- Leaking Cylinders: Leaks around the cylinder seals indicate a problem with the seals. Rebuild or replace the cylinder.
- Leaking Pump or Valves: Leaks from the hydraulic pump or valves indicate internal damage. Rebuild or replace the component.
Important Tip: Always relieve hydraulic pressure before disconnecting any hydraulic lines.
Drive System Problems: Track Issues and Loss of Mobility
The drive system allows your T870 to move around the job site. Problems here can leave you stranded.
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Track Issues?
- Track Tension: Tracks that are too loose or too tight can cause problems. Adjust the track tension according to the manufacturer's specifications.
- Track Damage: Inspect the tracks for cuts, tears, or missing lugs. Replace damaged tracks.
- Track Slippage: Slipping tracks indicate a loss of traction. This can be caused by worn tracks, loose tracks, or soft ground conditions.
- Debris in Tracks: Clean debris from the tracks regularly. Rocks, mud, and other debris can damage the tracks and reduce traction.
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Loss of Mobility?
- Hydraulic Drive Motor Problems: A failing hydraulic drive motor can cause a loss of power to one or both tracks. Have the motors tested and repaired or replaced.
- Hydraulic Leaks in Drive System: Hydraulic leaks in the drive system can cause a loss of pressure and reduced mobility.
- Parking Brake Issues: Ensure the parking brake is fully released before attempting to move the machine. A stuck parking brake can prevent movement.
Electrical System Glitches: Lights, Gauges, and ECM Issues
The electrical system controls various functions of the T870. Problems here can range from minor annoyances to major malfunctions.
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Lights Not Working?
- Blown Bulbs: Check the bulbs and replace any that are blown.
- Faulty Wiring: Inspect the wiring for damage or loose connections.
- Blown Fuses: Check the fuses and replace any that are blown. Use the correct amperage fuse.
- Faulty Switch: A faulty light switch can prevent the lights from working.
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Gauges Not Working?
- Faulty Sensors: Gauges rely on sensors to measure various parameters. A faulty sensor can cause the gauge to display incorrect readings or no reading at all.
- Faulty Wiring: Inspect the wiring to the gauges for damage or loose connections.
- Faulty Gauge: A faulty gauge can display incorrect readings or no reading at all.
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ECM (Engine Control Module) Issues?
- Warning Lights: If the ECM detects a problem, it will illuminate a warning light on the dashboard.
- Diagnostic Codes: The ECM stores diagnostic codes that can help identify the source of the problem. Use a diagnostic scanner to retrieve the codes.
- ECM Failure: In rare cases, the ECM itself can fail. This is a serious problem that requires professional diagnosis and repair.
Important Tip: Consult your operator's manual for the location of fuses and relays.
Cooling System Overheating: Preventing Engine Damage
Overheating can cause serious engine damage. Here's how to prevent it:
- Low Coolant Level: Check the coolant level and add coolant as needed. Use the correct type of coolant specified in your operator's manual.
- Leaking Radiator or Hoses: Inspect the radiator and hoses for leaks. Repair or replace any leaking components.
- Clogged Radiator: Clean the radiator fins regularly to remove dirt, debris, and insects.
- Faulty Thermostat: A faulty thermostat can prevent the engine from reaching its operating temperature or cause it to overheat.
- Faulty Water Pump: A failing water pump can't circulate coolant properly, causing the engine to overheat.
- Fan Problems: Ensure the cooling fan is operating properly. A faulty fan can't provide enough airflow to cool the engine.
Preventative Maintenance: The Key to Avoiding Problems
The best way to avoid problems with your Bobcat T870 is to perform regular preventative maintenance. This includes:
- Following the Manufacturer's Recommended Maintenance Schedule: Consult your operator's manual for the recommended maintenance intervals.
- Checking Fluid Levels Regularly: Check the engine oil, hydraulic fluid, coolant, and fuel levels regularly.
- Changing Filters Regularly: Change the engine oil filter, fuel filter, air filter, and hydraulic filter at the recommended intervals.
- Greasing Moving Parts: Grease all moving parts regularly to reduce friction and wear.
- Inspecting Hoses and Belts: Inspect hoses and belts for cracks, wear, or damage. Replace any damaged components.
- Cleaning the Machine Regularly: Clean the machine regularly to remove dirt, debris, and insects.
Frequently Asked Questions
- Why is my Bobcat T870 losing hydraulic power? Low fluid levels, clogged filters, or a failing hydraulic pump are common causes. Check these first.
- What does it mean when my Bobcat is blowing black smoke? This usually indicates an issue with the fuel-air mixture, often due to a dirty air filter or faulty injectors.
- How often should I change the hydraulic fluid in my T870? Refer to your operator's manual, but typically every 1,000 hours or annually, whichever comes first.
- Why are my Bobcat T870 tracks slipping? Loose tracks, worn tracks, or operating on soft ground can cause slippage. Adjust track tension and inspect for wear.
- What type of oil should I use in my Bobcat T870 engine? Consult your operator's manual for the recommended oil type and viscosity based on your operating conditions.
Conclusion
Troubleshooting your Bobcat T870 requires a systematic approach and a basic understanding of its key systems. By following the tips and solutions outlined in this guide, you can diagnose and resolve many common problems, keeping your machine running smoothly. Remember that preventative maintenance is the best way to minimize downtime and extend the life of your T870.