John Deere 310A Won’t Start – Troubleshooting and Solutions

[MikePhua]

Introduction
A John Deere 310A backhoe loader is a powerful and reliable machine, but like any piece of equipment, it can encounter issues that prevent it from starting. If you're experiencing problems with starting your 310A, it’s important to perform a methodical troubleshooting process to identify and resolve the issue. This article outlines the common causes for starting issues on the John Deere 310A and offers solutions to help you get your machine running again.
Common Causes for Starting Issues

1. Battery Problems
   • Symptoms: A dead or weak battery is one of the most common reasons a machine won't start. If the starter motor isn’t engaging or the lights are dim, the battery could be the culprit.
     
   • Solution: First, check the battery voltage. If it’s below 12.5 volts, the battery may need to be recharged or replaced. Inspect the battery terminals for corrosion and ensure they are clean and tightly connected. If the battery is old, it may need replacing.
     
2. Starter Motor Issues
   • Symptoms: If you hear a clicking sound but the engine doesn’t turn over, or if there’s no sound at all when trying to start, the starter motor might be faulty.
     
   • Solution: Check the connections to the starter motor and ensure the wiring is intact. You can test the starter motor by bypassing the solenoid to check if it functions. If the starter motor is faulty, it will need to be replaced.
     
3. Fuel Delivery Problems
   • Symptoms: If the engine cranks but doesn’t start, it could indicate a fuel delivery issue. This could be due to a clogged fuel filter, a faulty fuel pump, or air in the fuel lines.
     
   • Solution: Inspect the fuel filter and fuel lines for clogs. If the filter is dirty, replace it. Ensure that the fuel pump is working correctly, and check for any air pockets in the fuel system. Bleed the fuel lines if necessary to ensure proper fuel delivery.
     
4. Glow Plug Malfunction
   • Symptoms: If you’re experiencing starting issues during cold weather, the glow plugs may not be working correctly. This is especially true for diesel engines like the one in the John Deere 310A.
     
   • Solution: Test the glow plugs for continuity using a multimeter. If any of the plugs are faulty, replace them. Also, ensure that the glow plug relay and control circuits are functioning properly.
     
5. Ignition Switch Issues
   • Symptoms: If the engine doesn’t crank at all when you turn the key, the ignition switch may be the problem.
     
   • Solution: Inspect the ignition switch and its wiring for any faults. If the switch is defective, it may need to be replaced. Ensure all electrical connections are secure and free of corrosion.
     
6. Safety Switch Malfunctions
   • Symptoms: John Deere 310A loaders are equipped with various safety switches (such as neutral safety switches and seat switch) that prevent the engine from starting if they detect a potentially unsafe condition.
     
   • Solution: Check if the neutral safety switch or seat switch is malfunctioning. For example, the neutral safety switch ensures the machine won’t start if it’s not in neutral. Make sure the switches are functioning properly and are not stuck in a position that prevents starting.
     
7. Fuses and Relays
   • Symptoms: If all else seems to be working and the engine still won’t start, there may be a blown fuse or a faulty relay preventing the system from receiving power.
     
   • Solution: Check all fuses related to the starting system, including fuses for the fuel system, starter relay, and ignition system. If any fuses are blown, replace them. Similarly, check relays for signs of wear or malfunction.
     
8. Engine Compression Issues
   • Symptoms: A cranking engine that doesn’t start can also be caused by low compression, which may result from worn piston rings, valve issues, or a damaged cylinder head.
     
   • Solution: Perform a compression test to determine if the engine has sufficient compression. If compression is low, further inspection of the internal engine components will be required, and repairs may be necessary.
     

Step-by-Step Troubleshooting Guide

1. Check Battery and Connections
   • Ensure the battery is fully charged (over 12.5 volts).
     
   • Inspect the battery terminals for corrosion and clean if necessary.
     
   • Tighten any loose connections.
     
2. Test Starter Motor
   • Check for signs of a faulty starter, such as clicking or no sound when attempting to start.
     
   • Test the starter motor by bypassing the solenoid or using a direct connection.
     
3. Inspect Fuel System
   • Check the fuel filter and fuel lines for clogs.
     
   • Ensure the fuel pump is operating correctly.
     
   • Bleed the fuel system to remove any air pockets.
     
4. Examine Glow Plugs (if applicable)
   • Test each glow plug with a multimeter to check for continuity.
     
   • Replace any faulty glow plugs.
     
5. Verify Ignition Switch
   • Inspect the ignition switch and its wiring for any signs of wear or damage.
     
   • Replace the ignition switch if it’s malfunctioning.
     
6. Check Safety Switches
   • Inspect neutral safety switches, seat switches, and other safety-related switches for malfunctions.
     
   • Replace any faulty safety switches.
     
7. Test Fuses and Relays
   • Check fuses related to the starting system and replace any that are blown.
     
   • Test relays for signs of malfunction and replace as necessary.
     
8. Perform Compression Test
   • If the engine cranks but doesn’t start, perform a compression test to determine if there’s an issue with engine compression.
     
   • Repair internal engine components if compression is low.
     

Conclusion
Starting issues with the John Deere 310A can be caused by several different factors, from electrical problems to fuel system malfunctions. By methodically troubleshooting each system and component, you can pinpoint the source of the problem and take appropriate action to fix it. Whether it’s replacing a dead battery, fixing a faulty starter motor, or addressing fuel delivery issues, these steps should help you get your John Deere 310A back to work efficiently.