7 hours ago
When a Bobcat 863 skid steer refuses to start, it can be frustrating and concerning, especially on a busy construction site. The 863 is a reliable machine, but like any piece of heavy equipment, it can experience various mechanical and electrical issues that prevent it from starting. This article provides a step-by-step guide to diagnosing and resolving the issue, drawing on common causes and solutions used by professionals in the field.
Step 1: Check for Fuel System Issues
The first thing to verify when an engine fails to start is the fuel system. The Bobcat 863, like many other skid steers, relies on a consistent flow of fuel to the engine. If the fuel system is obstructed, clogged, or malfunctioning, the engine may fail to start.
Fuel Filter Clogs
A clogged fuel filter is a common cause of a no-start issue. Over time, dirt, debris, and contaminants can accumulate in the filter, preventing the fuel from reaching the engine.
If the fuel pump is not functioning properly, it can prevent fuel from reaching the engine.
A weak or dead battery is another common culprit when a machine won’t start. Even if the machine seems to be turning over, if the battery doesn’t have enough power, the engine may fail to ignite.
Battery Voltage
Start by testing the battery voltage using a multimeter.
Corroded or loose battery terminals can prevent the proper flow of electricity. Inspect the battery cables for corrosion or loose connections.
If the battery is in good condition and the fuel system is functioning, the next thing to check is the starter motor and solenoid. The starter motor is responsible for cranking the engine, and if it fails, the engine won’t start.
Starter Motor Condition
The solenoid is the switch that activates the starter motor. If the solenoid is faulty, it can prevent the starter from engaging.
Electrical components such as fuses and relays play a critical role in the starting system. A blown fuse or malfunctioning relay can prevent the Bobcat 863 from starting.
Fuses
If the fuel system, battery, starter, and electrical components are all functioning correctly, it’s time to inspect the ignition switch and safety interlocks. Many modern machines, including the Bobcat 863, are equipped with safety features that prevent the engine from starting if certain conditions are not met.
Ignition Switch
Safety interlocks, such as the seat switch, tilt sensor, and neutral switch, prevent the engine from starting under unsafe conditions. If any of these interlocks are engaged or faulty, the engine will not start.
For Bobcat 863 models with diesel engines, glow plugs play a critical role in the starting process, particularly in cold weather. If the glow plugs are malfunctioning, the engine may fail to start.
If the engine still doesn’t start after checking the fuel system, battery, starter, and electrical components, the issue could lie with the fuel injectors. Fuel injectors can become clogged or fail to deliver the proper amount of fuel to the engine.
If you’ve gone through all of the steps above and the Bobcat 863 still won’t start, it may be time to call in a professional. There could be an underlying issue with the engine, such as a timing problem or a deeper electrical malfunction, that requires advanced diagnostic tools and experience to resolve.
Conclusion
The Bobcat 863 is a reliable machine, but like all heavy equipment, it requires regular maintenance and timely repairs. By following the steps outlined in this guide, you can troubleshoot most starting issues with your machine. From checking the fuel system to inspecting the electrical components, each step will help narrow down the cause of the problem. If all else fails, don’t hesitate to reach out to a professional technician for assistance.
Step 1: Check for Fuel System Issues
The first thing to verify when an engine fails to start is the fuel system. The Bobcat 863, like many other skid steers, relies on a consistent flow of fuel to the engine. If the fuel system is obstructed, clogged, or malfunctioning, the engine may fail to start.
Fuel Filter Clogs
A clogged fuel filter is a common cause of a no-start issue. Over time, dirt, debris, and contaminants can accumulate in the filter, preventing the fuel from reaching the engine.
- Inspect the fuel filter for any signs of clogging or blockage.
- If the filter appears dirty or clogged, replace it with a new one.
If the fuel pump is not functioning properly, it can prevent fuel from reaching the engine.
- Listen for the sound of the fuel pump when you turn the ignition key. If you don't hear the pump engage, it could be faulty.
- Check for any fuel leaks around the fuel pump and fuel lines.
- Consider testing the pump with a fuel pressure gauge to ensure it’s delivering the correct pressure.
A weak or dead battery is another common culprit when a machine won’t start. Even if the machine seems to be turning over, if the battery doesn’t have enough power, the engine may fail to ignite.
Battery Voltage
Start by testing the battery voltage using a multimeter.
- The battery should show at least 12.5 volts when fully charged.
- If the voltage is below 12 volts, recharge or replace the battery as needed.
Corroded or loose battery terminals can prevent the proper flow of electricity. Inspect the battery cables for corrosion or loose connections.
- Clean the terminals with a wire brush and reconnect them tightly.
- If the cables appear frayed or damaged, replace them.
If the battery is in good condition and the fuel system is functioning, the next thing to check is the starter motor and solenoid. The starter motor is responsible for cranking the engine, and if it fails, the engine won’t start.
Starter Motor Condition
- Check the starter motor for any signs of wear or damage.
- If you hear a clicking sound when turning the key, but the engine doesn’t turn over, the starter motor may need to be replaced.
The solenoid is the switch that activates the starter motor. If the solenoid is faulty, it can prevent the starter from engaging.
- Test the solenoid by using a multimeter to check for continuity.
- If the solenoid shows no continuity or is defective, it will need to be replaced.
Electrical components such as fuses and relays play a critical role in the starting system. A blown fuse or malfunctioning relay can prevent the Bobcat 863 from starting.
Fuses
- Inspect the fuses in the fuse panel for any signs of damage or blown fuses.
- Replace any blown fuses with the appropriate amperage fuse as specified in the owner’s manual.
- Test the relays related to the starter system.
- Swap relays with other similar ones in the panel to see if the issue persists.
If the fuel system, battery, starter, and electrical components are all functioning correctly, it’s time to inspect the ignition switch and safety interlocks. Many modern machines, including the Bobcat 863, are equipped with safety features that prevent the engine from starting if certain conditions are not met.
Ignition Switch
- Test the ignition switch by checking for continuity with a multimeter.
- If the switch is faulty, replace it with a new one.
Safety interlocks, such as the seat switch, tilt sensor, and neutral switch, prevent the engine from starting under unsafe conditions. If any of these interlocks are engaged or faulty, the engine will not start.
- Check each interlock for proper operation.
- Make sure the machine is in neutral and that the seat switch is properly engaged.
For Bobcat 863 models with diesel engines, glow plugs play a critical role in the starting process, particularly in cold weather. If the glow plugs are malfunctioning, the engine may fail to start.
- Test each glow plug using a multimeter to check for continuity.
- If a glow plug is faulty, replace it.
If the engine still doesn’t start after checking the fuel system, battery, starter, and electrical components, the issue could lie with the fuel injectors. Fuel injectors can become clogged or fail to deliver the proper amount of fuel to the engine.
- Use an injector cleaner to clear any blockages.
- If the injectors are still malfunctioning, they may need to be replaced.
If you’ve gone through all of the steps above and the Bobcat 863 still won’t start, it may be time to call in a professional. There could be an underlying issue with the engine, such as a timing problem or a deeper electrical malfunction, that requires advanced diagnostic tools and experience to resolve.
Conclusion
The Bobcat 863 is a reliable machine, but like all heavy equipment, it requires regular maintenance and timely repairs. By following the steps outlined in this guide, you can troubleshoot most starting issues with your machine. From checking the fuel system to inspecting the electrical components, each step will help narrow down the cause of the problem. If all else fails, don’t hesitate to reach out to a professional technician for assistance.
