MF 135 hydraulic problems

[stapleford]

Hi all
Newbie here, looking for advice on strange issue we had with our loader tractor today.
Picked up loaded trailer and tipped it today, dropped off from hitch on 3 point ok but further down the field in first gear, rear hitch started to jump up and down (just the slack slack) in time with wheels turning. Stopped and it stopped, startrted again and it felt like something was binding the drive in time with the hyd going up and down reverse and same happned. Checked as thought linkage was touching a wheel or ground but no?
it stopped doing it but now cant raise or lower lift arms and they are only 3/4 way up, even if it take the hitch off leaving just the arms and stand on them. They will physically lift up to the top position by hand. Front EL off centre valve block still works, albeit slow and with reduced power if any load is put on it stops lifting and when lifting stops, i can hear relief going even though just b4 this problem, the loader could lift 1 ton with ease and take the rear wheels off the ground if they had no ballast. So question is, how can the rear links be conncted to the rear drive and how can the loader be tripping the relief too early now and not lifting the rear link arms up to top position first as would normally happen
Checked oil level ok in back axle any advice appreciated before we strip it next weekend but assume that the valve levers and/or cam have somehow contacted the rear diff and got bent?
Nige
UK

 

[Soundguy]

have you checked yer hyd oil?

lift jumping with rear wheel revoloution is semi normal for a belly pump setup like many ferguson systems used.. almost sound slike oil starvation.. and / or stuck relief. ( stuck open )

post back what you find on oil level

soundguy

 

[banjodunn]

G'day check the position of your draft contol lever make sure it is in the constant pumping pos if you have a diverter valave for the loader


Jon

 

[stapleford]

Hi guys
Thanks for the posts
The oil level is fine in fact on max, and it picked up a loaded trailer on the rear hitch and tipped it fine and I had dropped it off and was further down the field in first gear when the problem appeared. It caused the tractor to jerk as the arms jumped a couple of inches up and down as though on a cam off the back wheels which is why I initially thought the linkage had somehow contacted a rear wheel causing it to be jammed. I reversed and same happened


Now I have no movement up or down on the rear lift arms and they are not fully up either. I have both the draught and lift levers fully back as normal for loader i.e. constant pumping with divert valve in loader. This will cause lift arms to lift to top position usually before the loader will lift
Even this doesn稚 happen. Loader lifts but is slow and has limited power
Having studied some drawings, I fear that the internal lift arm valve linkage has contacted the differential gearing and got mangled hence loss of rear link arm control and possibly debris is now in the pump filter and or relief
We are going to strip the top off on Saturday so any links to drawings etc to help would be appreciated as we are a small volunteer society
thanks
Nige

Pic of me working on the 135 digging out old trackbed prior to reballasting with new stone and relaying track in 2008

 

[stapleford]

Ok
Took the top off today and found that the connecting ball jointed arm between lift cylinder and lift arm crank had become detached and got slightly chewed in the diff crown wheel. Fortuantely no serious damage
l
The question now is how does the rod stay retained if the lift arms are lifted and ram is not pressurised or should thsi never happen.

I believe it happened when someone lifted the hook hitch by hand while the link arms were lowered. There is a groove in the ball where it locates in the cranked arms but there was no circlip in there unless its somewhere under the diff
This then caused the lift arms to bounce up and down off the diff and piston to pop outs hence lower oil pressure available to the FEL via combiner valve

It looks like it will all go back together ok but is there any online drawings of this lot showing how it is all put together
the only bit that fell apart is the little piston valve that sits next to the lowering speed adjustment handle which seems to have lost its ball as assume its not just a spring in there?

The valve control rods also had long external compression springs that detached and looking at the rod ends, there are holes drilled as though retaining pins should have been fitted to hold the springs in place?

I am hoping we can just reassemble with new seals and clean oil as it was 8 years old and emulsified. Any advice appreciated
Nige

 

[Soundguy]

on an old ferguson or a ford, the dogbone rides loose in the cyl/piston, and is pinned to the rockshaft

soundguy

 

[soulasphil]

Hope this will help you.

 

[stapleford]

on an old ferguson or a ford, the dogbone rides loose in the cyl/piston, and is pinned to the rockshaft

soundguy

Hi thanks both for the replies and drawings
However, the dog bone end that locates in the lift arm rockshaft looks different
to tha drawing and locaes inside a socket on the rock shaft. Aprt from a groove on the ball, i cant see anything that could be used to locate i.e no pinning holes
should there be a circlip in the groove?
Regards
Nige

 

[Soundguy]

has to be something, or else the dogbone would fall out i fhte lift arms rotated up..

any cross holes?

soundguy

 

[stapleford]

has to be something, or else the dogbone would fall out i fhte lift arms rotated up..

any cross holes?

soundguy

no
just a groove that would take an external circlip but dont understand how that could keep it retained inside the lift arm crank socket