Mf40 front loader hydraulic lever seized.

[Jaypat88]

I noticed the lever that raises and lowers the bucket has seized. It will not budge even after hitting it lightly with a hammer. How do I fix it?

 

[Jim.ME]

Some history would help.

What model loader?

Not a "joystick" controlled valve, correct?

Is it the OEM valve as far as you know?

When was it last run and has it been setting?

Did this happen all at once or has it been developing as in moving harder?

Is the lever what is seized or does everything move until you reach the spool in the valve body?

Is the valve mounted vertically?

What have the temperatures been the past few days?

Also is this the boom lever (raises and lowers the boom to which the bucket attaches) or the bucket lever (rolls the bucket back and dumps it)? Proper ID is helpful as there are differences in the two valves that could be in play.

This post was edited by Jim.ME on 12/23/2022 at 03:58 am.

 

[RM-MN]

Do you have any water in the hydraulic oil that may have frozen? If so, wait for warmer weather or just gently heat the control.

 

[Jaypat88]

Temperature dropped really fast yesterday to 12 degrees.



This is a 71 MF40 with original front loader.



The lever in question is the boom lever.



The tractor has been sitting outside and was last driven 6
months ago.



I have noticed that the boom lever leaks slightly.



I have also noticed that occasionally the lever gets stuck
in one position as if it was moved too far but it easily
pushed back in correct position.



I will wait for warmer weather and see if that makes a
difference.

 

[Jaypat88]

Sorry, the loader is a MF34

 

[Jim.ME]

(quoted from post at 09:56:35 12/23/22) Sorry, the loader is a MF34

Guessing this is the original valve mounted vertically.

Warm the cap that covers the bottom end of the boom spool with a propane torch, heat gun, etc. My first guess is it has collected some water in it and has frozen with the temperature drop, forming an ice block around the detent mechanism at the end of the boom spool which is preventing movement. If warming it up frees that spool to move, remove the cap and clean the water and crud out of it, then re-install it. Do not hammer on things or you will have bigger problems.

If the boom valve was sticking in a position when you pushed it way forward to where it stops, that should be the detent held float position. It is supposed to lock in that position to allow floating the bucket over the ground, as it releases pressure from both sides of the boom cylinders. It would pull back up of that position relatively easy if the detent is working and properly adjusted. The detent mechanism has come apart or broken, it can bind the valve. First thing to eliminate is the water/ice possiblitity.