720 CH John Deere: Identifying and Solving Common Issues

[MikePhua]

The John Deere 720 CH is a classic and reliable machine known for its performance in agriculture and construction applications. However, like any heavy equipment, it can encounter issues that may affect its operation. This article provides an overview of the common issues faced by operators and offers troubleshooting solutions for the John Deere 720 CH.
Common Issues with the John Deere 720 CH

1. Starting Problems
   One of the most common issues that users encounter with the John Deere 720 CH is difficulty starting the machine. This could be due to several factors, including a weak battery, clogged fuel lines, or faulty ignition components.
   • Battery Issues: A weak or dead battery can prevent the machine from starting properly. This can often be identified if the engine turns over slowly or doesn’t turn over at all when attempting to start.
     
   • Fuel Delivery Problems: Clogged fuel lines or a malfunctioning fuel pump can prevent the engine from receiving the necessary fuel. Inspecting the fuel system for leaks and blockages can help resolve this issue.
     
   • Ignition System Failure: A faulty ignition coil, spark plugs, or starter relay could lead to starting issues. Inspect and replace any worn or damaged components in the ignition system.
     
   Solution: If the machine is experiencing starting issues, begin by checking the battery charge and connections. Replace the battery if necessary. Follow by inspecting the fuel system and cleaning or replacing filters as required. Lastly, test the ignition components and replace any faulty parts.
   
2. Hydraulic System Malfunctions
   Hydraulic issues are common in older machines, and the John Deere 720 CH is no exception. Symptoms of hydraulic problems include reduced lift capacity, slow or unresponsive hydraulic functions, or unusual noises from the hydraulic pump.
   • Low Hydraulic Fluid: Low fluid levels can cause the hydraulic system to perform poorly, potentially leading to machine failure if left unchecked.
     
   • Hydraulic Leaks: Leaks in the hoses, seals, or pumps can reduce hydraulic pressure and affect performance.
     
   • Clogged Filters: Clogged hydraulic filters can restrict fluid flow, causing slow or unresponsive hydraulic movements.
     
   Solution: Start by checking the hydraulic fluid levels and topping them up if necessary. Inspect the system for visible leaks and replace any damaged hoses or seals. Clean or replace clogged filters to ensure proper fluid flow. Regular maintenance of the hydraulic system is crucial to maintaining optimal performance.
   
3. Engine Overheating
   Engine overheating can be a significant issue, especially during heavy operations. The John Deere 720 CH is equipped with a cooling system designed to maintain optimal engine temperature, but problems such as a failing radiator, low coolant levels, or a malfunctioning water pump can lead to overheating.
   • Coolant Leaks: Leaks in the radiator, hoses, or water pump can cause coolant loss, leading to engine overheating.
     
   • Clogged Radiator: A clogged radiator can restrict airflow and reduce the cooling system’s efficiency.
     
   • Faulty Thermostat: A malfunctioning thermostat may not open or close properly, preventing the engine from reaching the proper temperature.
     
   Solution: Regularly inspect the radiator and cooling system for leaks and blockages. Ensure the coolant levels are sufficient and replace any worn or damaged hoses. If the radiator appears clogged, clean it thoroughly or consider replacing it. If the engine continues to overheat, inspect the thermostat and replace it if necessary.
   
4. Transmission Problems
   Transmission issues in the John Deere 720 CH can manifest as difficulty shifting gears, slipping gears, or strange noises from the transmission area. These problems are often caused by low transmission fluid, worn transmission components, or improperly adjusted linkage.
   • Low Transmission Fluid: Insufficient fluid can lead to poor shifting and damage to transmission components.
     
   • Worn Clutch: A worn-out clutch can cause the machine to have difficulty shifting or make strange noises when changing gears.
     
   • Faulty Linkage: Improperly adjusted or damaged linkage can result in difficulty engaging gears or a lack of response when shifting.
     
   Solution: Check the transmission fluid levels and top them up if necessary. Inspect the transmission for leaks and replace any damaged seals or gaskets. If shifting issues persist, inspect the clutch for wear and replace it if needed. Lastly, check the linkage and adjust or replace components if they are causing shifting problems.
   
5. Electrical System Issues
   The electrical system in the John Deere 720 CH controls various functions, including the starter, lighting, and other key components. Electrical problems may manifest as blown fuses, faulty switches, or issues with the machine’s battery charging system.
   • Blown Fuses: If the machine is not starting or electrical components aren’t functioning, it could be due to a blown fuse.
     
   • Faulty Alternator: A malfunctioning alternator can lead to a dead battery, as it may not be charging the battery properly.
     
   • Worn Electrical Wiring: Old or damaged wiring can cause electrical shorts or intermittent connections, leading to unreliable operation of electrical components.
     
   Solution: Begin by checking all fuses and replacing any that are blown. Test the alternator to ensure it is charging the battery correctly. Inspect the wiring for damage and repair or replace any worn or broken connections. It is also advisable to clean any corrosion from battery terminals to ensure proper power flow.
   

Preventative Maintenance Tips
To minimize downtime and ensure the longevity of your John Deere 720 CH, regular maintenance is essential. Here are some preventative maintenance tips:

1. Regular Inspections: Periodically inspect key components like the engine, hydraulics, transmission, and electrical systems to identify any potential issues before they become major problems.
   
2. Fluid Checks: Regularly check and replace fluids such as engine oil, hydraulic fluid, coolant, and transmission fluid according to the manufacturer’s recommended intervals.
   
3. Cleaning and Lubrication: Keep the machine clean, especially around moving parts and the undercarriage. Lubricate joints and components to prevent wear and improve performance.
   
4. Component Replacement: Replace any worn or damaged parts promptly to avoid further damage to the machine.
   

Conclusion
The John Deere 720 CH is a reliable and versatile machine, but like all heavy equipment, it is susceptible to common mechanical issues. By understanding the potential problems, such as starting issues, hydraulic malfunctions, overheating, transmission problems, and electrical system faults, operators can take the necessary steps to troubleshoot and repair the machine. Regular maintenance and timely repairs are key to ensuring the machine’s longevity and optimal performance, helping to reduce downtime and maximize productivity.