How to Prime the Fuel System on a JD310C Excavator

[MikePhua]

When using the John Deere JD310C excavator, users may encounter issues with the engine failing to start or running improperly, especially when there is an issue with the fuel system. One common cause is improper priming of the fuel system or air being trapped inside it. This article will explain the proper procedure for priming the fuel system on a JD310C and ensuring the system works correctly.
Check the Fuel System
Before beginning the priming process, it's essential to ensure that there are no issues with the fuel system. Inspect the fuel lines, filters, and fuel tank for any signs of leaks or blockages. Only proceed with priming if you confirm that the system is free of any obvious problems.
Priming Steps

1. Locate the Fuel Pump and Bleed Screw
   The fuel pump on the JD310C typically has a bleed screw located on the top or side. This screw is used to release air from the system and allow fuel to flow properly into the pump and injectors. Before starting any procedures, make sure the engine is turned off.
   
2. Loosen the Bleed Screw
   Using the appropriate tool, carefully loosen the bleed screw until you hear air escaping. This step will help release any trapped air in the fuel system, ensuring that fuel can flow smoothly into the pump and injectors.
   
3. Manually Prime the Fuel System
   Many JD310C machines are equipped with a manual priming pump. Use the manual pump to gradually pump until you see fuel begin to flow from the bleed screw. Make sure the fuel flowing out is steady and free of air bubbles.
   
4. Tighten the Bleed Screw
   Once the fuel flows steadily and without air bubbles, immediately tighten the bleed screw. This step ensures that the air is fully purged from the fuel system.
   
5. Check Fuel System Pressure
   After completing the priming process, start the engine and check the fuel system pressure. Ensure that the fuel pump is functioning properly and that there are no leaks or abnormal pressure readings. If the engine starts smoothly and operates normally, the fuel system has been successfully primed.
   

Potential Issues and Solutions

1. Fuel Not Flowing Smoothly
   If fuel does not flow smoothly during the priming process, the fuel filter might be clogged, or the fuel pump could be faulty. Inspect and replace the fuel filter, or check the fuel pump for proper function.
   
2. Difficulty Starting the Engine
   If the engine still doesn’t start after priming, it might indicate that air is still trapped in the fuel system. You may need to bleed the system again and check for any other issues in the fuel lines or filter. Additionally, check the battery and starting system to ensure they are functioning properly.
   

Conclusion
Priming the fuel system on the JD310C is a crucial step in ensuring the engine starts and runs smoothly. By following the proper priming procedure, you can purge air from the system and ensure uninterrupted fuel flow. Regularly checking and maintaining the fuel system is an important part of keeping your equipment in good working condition and avoiding costly repairs.