The hydraulic lift on your John Deere tractor is responsible for raising and lowering the hitch, attachments, or the mower deck. This is operated via the SVC control or joystick, which is normally to the left of the driver on the side of the tractor. This system uses hydraulics, or pressurized liquid to control the lift mechanism across nearly any application your garden tractor is built for. Unfortunately, dozens of things can go wrong with this system, as hydraulic valves, the hydraulic pump, the hydraulic lift control lever, and the control valve are all vulnerable to degradation, damage, or even sticking.
In addition, these problems affect any John Deere tractor lift with hydraulic function. This includes but is not limited to the John Deere 2240, 6410, 4010, and 6300.
If you’ve having problems with the hydraulic lift on your John Deere tractor, the problem can relate to dozens of parts in the system. However, troubleshooting your lift mechanism can always start with valve and pump problems as well as checking fluid levels and lines.
9 Issues in Hydraulic Lift of John Deere Lawn Tractor
If your John Deere’s hydraulic lift is not working properly, there are dozens of things that can go wrong. However, starting with the most likely is a good way to go – because you can often fix the problem fairly quickly. These 9 issues are the most likely.
1. Fluid Level
Fluid level issues are common and easy to fix. For example, you should actually change it every 1,200 hours of use. In addition, you sometimes have to refill the fluid, especially if your engine has problems or has sprung a leak.
To check the fluid level:
- Park the garden tractor on a flat space
- Run the engine at 1000 RPM for a few minutes
- Allow the engine to cool down for 3 minutes
- Either check the hydraulic fluid/oil sight glass or check the dipstick. This is normally located behind the driver’s seat. In some cases, you’ll have to remove the side panel and engine cover.
Refill the hydraulic reservoir using a funnel and appropriate hydraulic fluid. Your manual may recommend specific hydraulic oil. In most cases, John Deere recommends using its Hy-Gard hydraulic and transmission oil. When refilling, go slowly, being certain not to overfill the reservoir.
2. Fluid Pressure
Hydraulic systems should operate at PSI defined in the manual, which is an immense amount of pressure. If that pressure drops too low, your hydraulics won’t work. This is also easy to test, providing you have a model with a built-in hydraulic pressure gauge or have a separate pressure gauge available. In addition, you can find instructions on how to do so for your specific tractor in the user’s manual. For example, you can see how to test the hydraulic fluid pressure on the John Deere 318 here.
- Park the tractor on a flat surface
- Idle the engine
- Place all hydraulic control levers in a neutral position
- Connect a hydraulic pressure test kit rated for at least 2,000 psi, following the instructions from your manual and the kit
- Record the pressure
If the pressure is lower than is indicated in your manual, you’ll want to inspect the valves, the connections, and the leads. You’ll also want to check the oil level.
3. Drive Belt
Problems with the drive belt can prevent the input shaft from going up and down. Here, you can simply remove the engine cover, usually by lifting up the seat, to inspect the drive belt. If it’s cracked, broken, missing chunks, or stuck – replace it. Always be sure to follow safety protocols of parking your tractor, turning the engine off, and removing the red connection to the battery before removing the drive belt.
4. Air in System
If you’ve recently changed the hydraulic fluid, added more, or otherwise changed valves or lines in the hydraulic lift system, you must follow up by purging air from the system. Failure to do so can result in permanent damage to the hydraulic pump, sometimes within a few minutes of actuating the hydraulic lift. Here, most John Deere lawn tractors are designed to automatically bleed air out. You can do so by cycling the cylinders without actuating the hydraulics.
5. Charge Pump Issues
The hydraulic charge pump is responsible for moving fluid from the reservoir to the hydraulic system, for maintaining hydraulic pressure, and for maintaining hydraulic flow. If it fails, your hydraulic lift won’t work. Normally, you can test this using a basic hydraulic pressure test kit and by following the instructions in the user’s manual. For instance, you can find the instructions for the John Deere 318 here.
It’s extremely difficult to diagnose or fix hydraulic pump problems as a layman. If you:
- Inspect the pump for physical damage or deformed pistons
- Inspect the valves and lines for damage
- Using the instructions listed above, check the pressure on the system. It should be 850-975 PSI for most models. However, check your manual for specifications for your John Deere.
- Check the filters for clogs or buildup and if present, change or clean the filters.
- Idle the engine and listen. Actuate the hydraulics. Is there noise? Are cylinders turning?
Eventually, if your charge pump is having issues, it probably has to be replaced. You can always clean the filters, check the pressure, and check lines to ensure the issue isn’t coming from there. However, if the pump is damaged, it can’t usually be fixed.
6. Input Shaft Stuck or Broken
The input shaft or camshaft turns rotational motion into linear motion, allowing your hydraulic system to lift the hitch or the deck. If this is jammed or broken, it has to be fixed. Luckily, this is also an easy fix.
Physically inspect the camshaft. If it’s physically broken, you should notice fairly quickly. However, a physical breakage should require a significant amount of pressure or damage. You can also inspect connections at each end. Look for blockage, broken bolts, rust or other debris buildup, etc.
7. Relief Valve Stuck Open or Damaged
The relief valve in your John Deere garden tractor is intended to reduce pressure on the hydraulics system to prevent overload. However, if it’s set too low, your system won’t work. If you don’t know what you’re doing, it’s always a good idea to take your tractor to a professional.
- Check that the relief valve is opening and closing properly
- Check that the relief valve is not physically damaged
It’s also an option that you may want to replace the relief valve. You might also want to try releasing the valve completely and then tightening it back to “cracking” pressure. Doing so means you’ll need a hydraulic pressure gauge, caps for the lines, and an Allen or hex bolt matching the pressure gauge on your lift. However, as with other hydraulic adjustments, John Deere normally recommends that you have a professional do the work – both to avoid injury and to avoid potentially over-pressurizing your system.
8. Leaking Hydraulics
Whether your lift cylinder, the control valve, or the lines, leaking hydraulics will cause complete system failure. Luckily, leaks are also normally easy to diagnose. However, resolving them will vary depending on where the leak is.
With the engine off, inspect the hydraulic lift and the ground under the tractor for hydraulic fluid. If you see fluid buildup around seals, the pump, or on lines, it’s a sign your hydraulic lift is leaking. Consider inspecting each individual connection to ensure everything is tight and well fitted. Here, seal and gasket failure is common. That’s especially true in certain models, where pump seals are known to have issues.
9. Lift Linkage Binding
If the lift linkage between the hydraulics and the hitch is binding or sticking, your tractor will have lift problems. This issue is similar to that found with the camshaft, because it’s likely either physically jammed, bent, or broke. Like with the camshaft, it’s extremely unlikely it would be physically broken, so inspecting connections, pins, and the mechanism to ensure it’s moving freely should be your first step.
Understanding Function of a Hydraulic Pump
The hydraulic pump generates and maintains pressure in a hydraulic system. It normally achieves this by creating a vacuum at the pump inlet and by forcing liquid into the hydraulic system to maintain pressure or to offset pressure caused by load weight.
Hydraulic Lift Won’t Go Up?
If your hydraulic lift won’t move at all, it could be dozens of reasons. However, you’re likely looking at a pressure issue or a blockage. For example, some users report similar issues when valve spools stick. Here, it’s always a good idea to manually inspect the hydraulic lift, check the spools, check the pins, and clean everything if you’re unsure.
Fixing hydraulic issues as a layman can be extremely difficult. Chances are, you still have questions.
How do you use a lift jack on a lawn mower?
Lift jacks normally fit under the back wheels and then lift the tractor from the side. This allows for easier and safer maintenance, providing you use the safety locks on the jack. To use the jack, pull the release on the back of the tractor so that you can manually roll it. Be sure to push the release back in before you attempt to use the tractor. Move the tractor onto the jack. Use the supplied straps to fasten the wheels to the jack. Lift the jack and insert the safety bar. Engage the safety locks. That’s it.
How much will a tractor front end loader lift?
Lift capacity heavily depends on what type of John Deere tractor you have. However, weights usually range from 500-5,000 pounds. You can check the official John Deere front loader chart to find your model and the attached front loader for more specific details.
If you want to troubleshoot John Deere tractor hydraulics, it’s always best to start with fluid pressure, fluid level, and mechanical parts. If you have a pressure gauge, you can also easily check pressure and flow rate. However, if there are no visible issues with your hydraulic lift system, it can be difficult to diagnose specific problems without a professional inspection.