Ford 3910 wheel braking by itself

[oliveiracarlos]

Hello all,

I have a Ford 3910 and it started to brake a bit the left wheel without braking.
When I leave the tractor in an inclined road facing forward with both levers in Neutral and no braking, the tractor starts moving by it self due to gravity.
But when I leave the tractor in an inclined road facing backwards with both levers in Neutral and no braking, the tractor moves a few inches but the I feel the left wheel braking by it self and stops.

Does anyone already had this defect, what can it be?

Thanks a lot for the support,
Carlos Oliveira

 

[TractorTech]

A lot of hours on this tractor? Are the brakes adjusted out and the actuator is worn.

The actuator is two plates sandwiching 4 balls that when you push the brake, roll the balls up the ramps pushing the plates out to engage the brakes discs. When the brakes get to the end of life, the balls could roll to the end of the ramp and stick.
Also possible, you may jus have the brake adjusted too tight or the wrong oil in the rear axle.

Thinking since I wrote all of this, do you have a broken spring on your left brake pedal?

 

[oliveiracarlos]

The tractor has already got lot of years and working hours.

The brakes seem to be adjusted and both pedals spring is OK. I´m using the Mannol STOU OIL 100-W30.

I will disassemble the brakes this weekend and check the actuator as you suggest.
It´s strange that this only happens when the tractor moves free backwards.

 

[TractorTech]

I'm guessing that the actuator is worn or maybe 1 or 2 springs that hold the 2 halves together are broken causing the actuator to drag on the discs.
Pictures when you find the problem would be great.

 

[oliveiracarlos]

Hello,

I´ve already disassemble and it seems OK to me, could you give me your opinion?
I´ve also got a video, but don´t know how to upload it.

 

[oliveiracarlos]

Video of the actuator in attached.

 

[TractorTech]

The picture of the steel discs shows overheating. The actuator ball ramps are cupped at the deepest point. I'm wondering if the brakes were adjusted too tight and the brakes were always just dragging on that side.

 

[oliveiracarlos]

I´ve tested them assembled again without any adjustment and the failure does not happen anymore.
It seems to me that it could be that they were in fact were adjusted too tight, i didn´t take that into consideration when I disassembled them.
I also noticed some dirt, in two of the spheres wholes, it looked like some small metal chips in it, and that could also make the spheres not to return correctly into their place.

I will now add the missing oil and adjust the brakes again to see if everything is OK.

By the way, any hint on how to correctly adjust the brakes?

Thanks for the support,

 

[TractorTech]

Glad to hear you resolved the problem. Make sure you use a hydraulic transmission oil with a friction modifier to prevent grabbing or squawking brakes.

Adjust the brakes so that you have about 3/4-1" free play in the brake pedals

 

[oliveiracarlos]

I´m using Mannol STOU OIL 100-W30. Super Tractor Oil Universal, they mention it´s good for wet brakes and hydraulics.