Troubleshooting Bobcat Running After Key is Switched Off: Causes and Solutions

[MikePhua]

Having machinery run after the key is turned off can be a frustrating issue, particularly when dealing with heavy equipment like Bobcat skid steers and compact loaders. This problem may seem alarming but is typically related to electrical or mechanical failures that can be diagnosed and resolved with some patience and know-how.
This article delves into the possible causes of a Bobcat continuing to run after the key is turned off, offering solutions and preventative measures to avoid future occurrences.
Possible Causes of Bobcat Running After Key is Off
There are several potential reasons why your Bobcat loader or skid steer might continue to run even after the key is switched to the off position. While the exact cause can vary depending on the model, age, and condition of the machine, common issues include:

• Faulty Ignition Switch: The ignition switch is one of the most common culprits. If the switch itself is faulty, it may not completely cut off the electrical supply to the engine when turned off. This means the machine might keep running even after the key is removed.
  
• Sticking Solenoid or Relay: The solenoid or starter relay is responsible for engaging the starter when the ignition is turned on. If the solenoid or relay gets stuck, it can keep the engine running even after the key is off. Electrical components like relays and solenoids may wear out over time or suffer from poor connections that cause them to malfunction.
  
• Electrical System Issues: Sometimes, the problem might not be with the ignition switch or the solenoid but with a short circuit or fault in the electrical wiring. Damaged wires or faulty connections could cause the machine to continue running.
  
• Diesel Engine After-Run: Some diesel engines are designed to run for a few seconds after the ignition is turned off. This process helps cool down the engine and reduces the risk of engine damage. However, if this feature is malfunctioning or if there is a persistent fuel issue, it might cause the engine to run for longer than necessary.
  
• Fuel System Issues: If the fuel shutoff valve or the fuel cut-off solenoid isn't working properly, the engine may continue running because it isn’t receiving the proper signal to shut off. Fuel system issues are common in older machines or those that haven’t been maintained regularly.
  

How to Diagnose the Problem
Diagnosing why your Bobcat continues running after the key is off involves a process of elimination. Here's how to troubleshoot the issue:

1. Inspect the Ignition Switch: Start by checking the ignition switch. If it's faulty, it might not be disconnecting the power supply when turned to the off position. Test the switch using a multimeter to see if it’s functioning properly. If necessary, replace the switch.
   
2. Check the Solenoid and Relays: Test the starter solenoid and any associated relays. Sometimes, a relay can get stuck in the closed position, causing continuous power flow to the engine. If the solenoid is sticking, it may need to be replaced.
   
3. Examine the Electrical Wiring: Inspect the wiring in your Bobcat for any visible damage, corrosion, or loose connections. Poor electrical connections can lead to a short circuit or continuous power being supplied to the engine. Ensure that all wires are properly insulated and securely connected.
   
4. Evaluate the Fuel System: If you suspect the fuel system is the issue, check the fuel shutoff valve and fuel cut-off solenoid. Ensure that the valve is operating correctly and that there are no blockages or leaks. If the fuel system isn’t properly cutting off the fuel supply, the engine will continue running.
   
5. Look for After-Run Issues: If your Bobcat has a diesel engine, it might have an after-run feature. If this is the case, check to ensure that it’s not malfunctioning and causing the engine to run excessively after the key is turned off. This feature is typically designed to run for a short period to cool down the engine, but it should not run indefinitely.
   

Common Fixes for Bobcat Running After Key is Off
Once you’ve identified the underlying cause of the issue, you can begin addressing it with the following fixes:

• Replace the Ignition Switch: If the ignition switch is found to be faulty, replacing it with a new, quality switch is the simplest solution. Be sure to choose an OEM (Original Equipment Manufacturer) switch to ensure proper compatibility and function.
  
• Clean or Replace the Solenoid and Relay: If the solenoid or relay is sticking, cleaning the components might solve the problem. However, in many cases, replacement is necessary. If you're unsure about how to test or replace these components, consider seeking professional help.
  
• Fix or Replace Damaged Wiring: If you’ve identified damaged wiring, replace the affected sections and ensure that all connections are tight and secure. Corroded or loose connections can often lead to electrical problems that prevent the ignition system from working as it should.
  
• Clean or Replace the Fuel Shutoff Valve: If you find that the fuel system is not shutting off properly, cleaning or replacing the fuel shutoff valve or solenoid is crucial. Be sure to use quality parts and consider having a professional inspect the fuel system if you're not comfortable handling the repair.
  
• Inspect the After-Run System: If your Bobcat uses an after-run system, check for any faults in the system’s wiring or sensors. Repair or replace any malfunctioning parts to ensure that the system runs only for the necessary duration.
  

Prevention and Maintenance Tips
Preventing the issue of your Bobcat running after the key is off is largely about regular maintenance and proper care of the electrical and fuel systems. Here are a few tips to help you avoid this problem in the future:

• Regularly Inspect Electrical Components: Make it a habit to inspect your Bobcat’s ignition switch, wiring, and relays. Keeping these components clean and free of corrosion will go a long way in ensuring they function properly.
  
• Change Filters and Fluids: Regular maintenance, including changing fuel filters and fluids, will help ensure the smooth operation of the fuel system and prevent issues like fuel cut-off malfunctions.
  
• Test the Solenoid Periodically: Check the solenoid and relays for proper function regularly. These components can wear out over time, so it’s best to replace them before they fail completely.
  
• Use Quality Fuel: Ensure that you’re using clean, high-quality fuel, especially in diesel engines. Contaminated or old fuel can cause fuel system problems that could prevent the engine from shutting off properly.
  
• Consult the Operator Manual: Always refer to your Bobcat’s operator manual for specific troubleshooting steps and maintenance schedules. The manufacturer’s guidelines are often the most reliable source of information.
  

Conclusion
If your Bobcat continues running after the key is turned off, it can be a concerning issue, but it's typically fixable with a bit of troubleshooting. Whether the problem lies in the ignition switch, solenoid, wiring, or fuel system, identifying the issue is the first step toward a quick resolution. With regular maintenance and proper care, you can avoid this problem and ensure that your Bobcat continues to perform reliably.
Remember, always seek professional help if you're unsure about handling electrical or fuel system repairs, as incorrect handling can lead to further damage or safety concerns.