3-Point Hitch Problem - Tractor Service Manual - How to Troubleshoot and Fix Tractor 3 Point Hitch Problems

Tractor Service Manual 3 Point Hitch Problems - How to Troubleshoot and Fix Tractor 3- Point Hitch Problems 

How to Fix a Tractor 3 Point Hitch - It isn’t working, and here is what may be wrong and how to fix it

One of the most common tractor repair questions that customers ask us is what is wrong and how to fix a tractor three point hitch.  Yes, we do have all the 3-point tractor parts in stock for Kubota, John Deere, Kioti, Yanmar, Mahindra, Kioti, Case, New Holland, Massey Ferguson, Ford, Deutz, Case IH, Farmall, International Harvester, Branson Tractors, LS, Shibura, Claas Tractor, McCormick Tractors, Valtra, Solis, YTO, Montana, Nortrac, Escorts Tractor, Belarus, Sonalika, Jinma, Mahindra, TYM, Apollo, Bolens, Fendt, Cub Cadet, Lamborghini, Iseki, Oliver, Mitsubishi Tractors, Same, Foton, Fiat, AGCO, White tractors and many more, however the very first step is to diagnose exactly what is wrong with the tractor hitch to know what is need to fix it. Who knows, as you will see in this article it may be just be a simple adjustment and can be fixed in 5 minutes.

Understanding the Function, Operation and Components of a Tractor 3 Point Hitch

A 3-point hitch functions by hydraulic lift which allows the operator to raise or lower the hitch and anything conected to the three-point hitch. More specifically, the 3-point lift allows the operator to operate and adjust the operating height of the three point hitch and tractor implements. The major tractor parts that operate the hitch include the hydraulic pump, hydraulic lift control lever, and the hydraulic control valve. Hydraulic oil pressure is generated by tractor’s hydraulic pump which is often located on the top of the transmission, in front of the engine, or is mounted on the side of the engine behind the front axle. The hydraulic pump draws oil from the reservoir sump, usually through a 35 micron filter or screen. Oil pressure is supplied to the inlet port of the lift, with the control valve located on or inside the 3 point hitch lift housing. 

This control valve is connected by linkage) to the 3-point lift control lever and lift arm, which opens and closes the control valves allowing hydraulic oil pressure to flow in and flow out, depending on the position of the control lever. Tractors also have a selective speed control valve that adjusts the rate of drop of the hitch. The tractor three point lift control lever is located to the side of the operator seat, adjust the height of the hitch up or down. Moving the lift control lever forward will allow the control valve to release oil out of the lift cylinder and lower the lift arms, and pulling the lever backwards flows hydraulic oil, under pressure, into the cylinder to raise the lift arms.

Diagnosing 3 Point Hitch Problems - What is your hitch doing and what is wrong?

• The tractor 3 Point Hitch won’t stay up and drifts or falls down
• The Tractor 3 Point Hitch won't go up at all
• The Tractor 3 Point Hitch stays up and won't go down
• The Tractor 3 Point Hitch goes down too slow

Tractor Three Point Hitch 3 Point Hitch Won’t Stay Up, Drifts Down, or Falls Down

When customers contact us for help with 3 point hitch problems, usually the first thing that we help to walk them through is trobleshooting the hydraulic system. When a tractor 3 point hitch doesn’t operate properly, many times low fluid, a clogged hydraulic filter, or low or contaminated hydraulic fluid is the cause of the problem. Because most tractor functions rely on the hydraulic system to power them, including the 3 point hitch, hydraulic filter and fluid maintenance has an important effect on every tractor’s operation. 

Specifically, the key elements to diagnose are i) is the hydraulic fluid reservoir full with the proper hydraulic oil (including type and viscosity); ii) have the filters been changed and the tank in-line strainers been thoroughly cleaned; and iii) are all the hydraulic fittings, connections, caps and vents tight so that so that air is not causing the pump to cavitate. 

The first step is to determine if the overall hydraulic system is operating properly. If the a loader is installed on the tractor, test the loader to make sure it is still working correctly, which can rule out any problem with the pump. If the loader does not operate correctly, then there is a problem is likey related to the hydraulic pump. IF YOUR TRACTOR S not equipped with a loader, disconnect the main pressure and return lines on the hydraulic pump and connect them together. Start and run the tractor for no more than 5 seconds. If the engine lugs down or will not start, or if the loader does operate correctly, the pump can be ruled out. 

The next step ist to check the 3 point control handle to make sure a rod or retaining pin didn't fall out of the handle. If all of these check out, then there is most likely a mechanical part failure inside the 3 point housing, and will require disassembly of the tractor rear end (see next section) 

Tractor Three Point Won't Stay Up or Leaks Down on its own

If the three point hitch will not stay up or leaks down on its own, try to lift the three point arm links all the way up and close the selective 3 point speed control valve, which is usually located under the tractor operator seat (between the operator knees). Close the speed control valve all the way to the stop, pull the tree point control handle all th way back, and then shut down the tractor. Try to raise the lift arms by hand. If the three point arms go up easily and seep down or fall down with no resistance, then there is most likely a bad seal, o ring, packing kit in the lift piston. By closing the speed control valve all of the way, you will have eliminated the valve itself and all of the parts of the system before this valve in the hydraulic circuit. If the three point stays up, this indicates that there is most likely a problem with the three point control valve.

Three Point is up and Will Not Go Down

When a three point hitch will not go down, the most frequent cause is the hydraulic flow speed control valve, usually located between your knees under the seat, is closed with the knob closed all the way to its stop. Check this control and make sure that the valve is all of the way open. If the valve is open, check that all of the linkage between the valve and the handle are attached and move freely. If all look good, the next step is to check the speed control valve itself. 

To check the valve, first remove any equipment or tractor implements from the three point so nothing attached to it. Make sure the tractor is shut off, and then unscrew the entire speed control valve assembly. BE CAREFUL - oil can will shoot out of the valve under pressure and could cause injury. Again, stay completely clear of the valve during this process. Once unscrewed, push down (gently) on the lift arms. A small check-valve that will pop out of the hole so be sure you have something there to catch it (other than your hand). If you get a stream of oil shooting out of where the lockout valve was installed and the three point goes down, then you have a blockage somewhere in the hydraulic valve system. Debris may have become plugged one or more of the hydraulic flow ports or fittings in the system. If so, the speed control valve will need to be completely removed to check to see if the three point goes down after removal. If it does, the 3 point hitch speed control valve is faulty. 

If the hitch does not drop after removing the valve, then there is a mechanical failure causing binding in the lift piston and or the shaft mechanism (Fig Parts# 2 - 12). Such tractor 3 point part failure is often caused by contamination of hydraulic oil with moisture or water for prolonged periods resulting in the accumulation of rust inside of the lift cylinder. Due to the 3 point lift cylinder polished surface, the presence of even the slightest amount of moisture in hydraulic fluid can result in oxidation and rush causing the lift piston to stick or bind. If this is the case, the lift piston and cylinder will need to be completely disassembled and inspected. If the cylinder walls and piston are slightly scared, we can recommend fine honing and polishing of the cylinder. If rust is present, replacement of the piston and cylinder parts is recommended.

Team Tractor Ranch - The Tractor Pros - we are here to help. For Tractor Parts or Service online, visit www.TeamTractor.com or give us a call anytime at 602-734-9944. Our folks are friendly, and our advice is free!