MF 135 lift arms issue

Dave_Mitchell · Aug 9, 2019

Hi all, new to the forum and looking for advice. I just got a MF 135 that had been sitting in a friends barn for years. The lift arms didn't work. We discovered the pump was bad. We put in a new pump and the lift arms will work fine without any weight or with a 450 lb counter weight on them. When we put a rotary cutter on and lift it the arms will go up, but will not go down.

We took the side plate off and the quadrant levers don't move the lever inside the tractor. We can move it forward with a screwdriver and then the arms come down. We tried moving the adjustment screws with no success. Can anyone offer any advice? Thanks in advance.

Brendon Warren · Aug 9, 2019

Could your quadrant levers be on the
wrong side of the roller on the pump?

DavidP, South Wales · Aug 10, 2019

Hello, if you have moved the adjustment
screws then you may have already
prevented the system from working in
addition to whatever is wrong. You have
mentioned SCREWS. Does the tractor have
pressure control? Raising the Position
Control lever on the quadrant should
allow the pump lever to move rearwards.
When you lower it it will push the pump
lever forwards. If this is not happening
there is a problem in the internal
linkage in the cover, seizure or a bent
frame perhaps. Ensure that the pump lever
(control valve) moves freely.
DavidP, South Wales

Dave_Mitchell · Aug 10, 2019

I think everything is working as it should. We used a shop manual to make sure everything was together properly. I'm not sure if I can post a video, but I can take a picture today of the quadrant lever down and up and how the control valve responds. Everything moves freely until under load, the quadrant levers then move, but the control valve lever doesn't.

I need to ask my friend again, but I'm pretty sure it has pressure control. The adjustment screw comes out the front of the pump lever. I believe the manual mentions adjusting it.

The arms work with 400 or so pounds on them. As long as the trailing wheel of the mower sits on the ground the arms go up and down. Once the entire mower is lifted, then it will not go back down.

DavidP, South Wales · Aug 10, 2019

Are you still testing this with the RH
side cover removed? If so, make sure that
the response quadrant lever is in the
FAST position. If not it won't matter.
DavidP

MF 135 lift arms issue

Dave_Mitchell

New User

Brendon Warren

Well-known Member

DavidP, South Wales

Well-known Member

Dave_Mitchell

New User

DavidP, South Wales

Well-known Member

Similar threads