John Deere 840 Operator's Manual V2
![John Deere 840 Sprayer manual cover](/images/TLDTQDPYdninxyReHlZMBiiT/thumbs/thumb175x175.webp)
To calibrate the spray rate, start by ensuring the sprayer is in a stationary position. Access the control panel and navigate to the calibration settings. Follow the on-screen instructions to input the desired spray rate and test it in a controlled environment. Adjust as necessary until the correct rate is achieved.
If the spray nozzles are clogged, remove them from the boom and clean them with warm water and a soft brush. Avoid using sharp tools that could damage the nozzles. Reinstall them and test the spray pattern to ensure proper functionality.
Improving fuel efficiency can be achieved by maintaining consistent spray speeds, reducing idling time, and ensuring the engine is regularly serviced. Keeping tires properly inflated and using the correct nozzle size can also contribute to better fuel economy.
Before storing the sprayer, clean all components thoroughly, especially the tank and nozzles. Drain any remaining liquids, lubricate moving parts, and check for wear and tear. Store in a dry, sheltered location to prevent damage from the elements.
To troubleshoot a hydraulic leak, first identify the source by inspecting hoses, connections, and fittings for signs of wear or damage. Tighten any loose fittings and replace damaged components. Use a UV dye in the hydraulic fluid to help identify small leaks.
Refer to the operator's manual for specific tire pressure recommendations, as these can vary based on the tire type and expected load. Generally, maintaining the manufacturer's recommended PSI ensures optimal performance and fuel efficiency.
If the boom is not extending, check for hydraulic issues such as leaks or low fluid levels. Inspect the boom for obstructions or mechanical damage. Ensure that the control valves are functioning correctly and are not blocked.
To change the oil, first warm up the engine to help the oil drain smoothly. Turn off the engine and remove the oil drain plug. Allow the old oil to fully drain, then replace the plug. Add new oil according to the specifications in the operator's manual, and check the level with the dipstick.
Signs that the pump may need servicing include reduced pressure, unusual noises, leaks, or a complete lack of fluid movement. Regularly check the pump for these symptoms and refer to the manual for specific troubleshooting steps.
To adjust the boom height, use the control panel to navigate to the boom settings. Select the desired height and adjust using the hydraulic controls. Ensure the boom is level and test the spray pattern to verify the height adjustment is correct.