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Writer's pictureAlexander Stuck

Stuck Hydraulic Lever

I have an opportunity to purchase a TO-30 which checks out fine except for the following: The 3 point hitch control lever is frozen in the straight up position, and the arms can be moved up or down manually. The control lever will not move. I Loosened the control lever retaining nut – no change. The PTO seems to work fine. I have looked at the schematics for the unit, but can’t quite see how everything. works together to raise the arms. Something is binding, bent, broken or worn in the linkage? I Need a tractor now to start plowing with and will pass on this one, but would appreciate any thoughts that you may have? April 22, 2015.


It’s very possible the problem is just a stuck lever. The lever is connected to a rod that has an offset or eccentric on the end. The offset or eccentric pushes against the fork linkage that is connected to the control spring plunger at the top and the hydraulic control valve at the bottom. The offset or eccentric on the aforementioned rod acts like a moving fulcrum.


If the tractor sits outside for an extended period and the lift lever is not moved, the lever can stick. You can remove the lift lever assembly by removing the 4 bolts that hold the quadrant assembly in place. You can then withdraw and remove the assembly, There is a hole in the quadrant assembly where the shaft passes through the bracket. Putting penetrating oil in the hole should help free it. You can also use some gentle heat but be careful because the hub where the left lever is bolted to the shaft is an aluminum alloy and will melt if you apply too much heat, Once the shaft/assembly is free you will have readjust it after it is installed.


This is an easy adjustment to make so don’t panic. The adjustment is shown in the operator’s manual and shop manual.


I can send you the information if you need it. There is also a friction washer between the hub where the lever is attached and the 4 hole bracket. This original friction washer on many of these tractors was made out of rubber. The rubber can harden or stick to its mating surfaces which also causes the lever to stick. Silicone spray lubricant will usually free up the rubber disc. A cork friction disc was also used and is now the common replacement. Adjust the castle nut to put just enough tension on the spring to hold the lever in position yet allow it to be moved easily.


The hub can be removed but it usually stuck to the shaft and requires a lot of patience and penetrating oil to remove. These hubs often break when attempts are made to remove them but after-market replacements are readily available.


There is a key in the shaft to keep the hub in position but once the hub and key are removed, the shaft can be pushed out of the 4 hole bracket. To make sure the rest of the internal linkage, the fork assembly, is working properly, remove the side cover where the dipstick for the transmission/rear axle is located. You should be able to move the fork assembly back and forth.


The entire system is relatively simple to service and usually does not require service unless the fork becomes disconnected from the “dog bone” link attached to the control valve. The disconnecting problem was eliminated on TO-30 models when an aluminum spacer block was added to keep the legs of the fork from spreading apart.

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