MF 135 Hydraulics stopped working

AndrewMF135 · Dec 21, 2016

Hello

Today my MF135 hydraulics just stopped working. I had been using them, then they just did not work.

The engine was running, I had been using them, then they did not work. I don't believe the stopped mid operation.

I heard nothing new, and can't see any new leaks.

The oil level shows as just over half full.

Both the auxiliary and the rear lift have stopped.

Unfortunately it has a loader and a backhoe attached, so it is stuck out in the open for the moment.

Has any one any idea what I should check out first?,

Regards

Andrew

AndrewMF135 · Dec 21, 2016

Update:
After a period (couple of hours) of not using machine, it suddenly worked! Fairly soon, while using the backhoe, it stopped again. There is no pressure withing the hydraulic system. As I switch back and forth the auxiliary diverter it moves easier that it has ever before. No hydraulics work, as before.

I have one potential scenario, which seems unlikely, but I would like comments on, please.

The backhoe is new to me (Woods 750). It had not been run by me for more that a few minutes. It is probable that it has hydraulic fluid rather than the oil the 135 hydraulics run on. I had assumed mixing the two would be fine, for a short while.
Could the pressure drop be when the pump encounters the hydraulic fluid? No too sure how it all hangs together.
Thanks.

shaeff · Dec 21, 2016

Have you checked the level of hydraulic oil in the transmission? Mixing a small amount shouldn't hurt since your tractor's transmission holds about 8 gallons of more. If you're low on fluid, you could potentially be starving the pump. At this point, all that fluid is likely well mixed together.

AndrewMF135 · Dec 21, 2016

Thanks for your reply. Yes I have checked it. It is just over half full, according to the dip stick.

shaeff · Dec 22, 2016

I'm not 100% sure how the hydraulics on the 135 function, but maybe your problem has something to do with the location of your draft or position control levers?

Do you hear a hissing sound from the pump area? If so, that would indicate that the relief valve is open, bleeding off all your pressure.

I've also never used a diverted valve, but I often see people on the forums having issues sorting out what position it must be in for one thing or another to function properly.

Losing all hydraulic function points to loss of pressure somewhere. Have you checked the filter screen? Is it free of debris? Is the hydraulic fluid foamy and look kindof like a milkshake? (Indicating water ingress). If the fluid is milky then it should be flushed.

AndrewMF135 · Dec 22, 2016

I'm still trying to find a way of getting the backhoe off as that stops me investigating any of the hydraulics, and I can't move the tractor into a dry space to work on it. My hydraulic failure has coincided with a turn in the weather. Hopefully I'll succeed tomorrow.

I'm pretty familiar with how to operate the hydraulics, I switch between draft control, loader, skidding winch and log-splitter all the time.

I didn't notice any sounds, but I'll check again tomorrow, It's dark and wet outside right now.

The dipstick had quite clean looking oil, but I'll whip the filler cap off tomorrow and have a look inside, weather permitting.

I do think I've lost pressure throughout, hence the diverter so easy to move

GAFarmer2 · Dec 22, 2016

It almost sounds like you're losing the pump itself. I had a TLB that would do the same thing. As soon as it heated up, the tolerances in the pump along with the thinning fluid from rising temps would stop me dead. I don't have any experience with the 135...hopefully it is something simple!

AndrewMF135 · Dec 22, 2016

Hello GAFarmer2.
Yes, that makes sense to me. Definitely a possible scenario.
If you are right then I might be able lift everything while it is cold and move it to a place I can work on it. I'll try it in the morning and let you know how I get on.
Thanks.

AndrewMF135 · Dec 23, 2016

Stranger and stranger, here is what just happened.

Started the tractor and tried the hydraulics in the hope of lifting the backhoe and strapping it up so I could move the beast. Hydraulics dead!
Used a tirfor winch to lift the backhoe, pulling against the front of the tractor, to get straps on it. That worked fine. Next I drove the tractor backwards, dragging the bucket, to get it undercover to work on. Decided to have another listen and play to see if I could detect anything when operating the loader, and, hey-presto, it's working!

I'm building a stand to mount the backhoe on, which may be ready for tomorrow, then I should be able to get backhoe off (hopefully with the help of the hydraulics). I can then investigate (the backhoe is fixed via the hydraulic cover).

So, not sure again what it can be. I reiterate, I'm pretty confident I have the controls in the correct position as I switch between them all every time I use it, pretty much.

I'll keep this posted with updates, and hopefully the final solution.

PatrickS2222 · Dec 24, 2016

AndrewMF135 said:
Stranger and stranger, here is what just happened.

Started the tractor and tried the hydraulics in the hope of lifting the backhoe and strapping it up so I could move the beast. Hydraulics dead!
Used a tirfor winch to lift the backhoe, pulling against the front of the tractor, to get straps on it. That worked fine. Next I drove the tractor backwards, dragging the bucket, to get it undercover to work on. Decided to have another listen and play to see if I could detect anything when operating the loader, and, hey-presto, it's working!

I'm building a stand to mount the backhoe on, which may be ready for tomorrow, then I should be able to get backhoe off (hopefully with the help of the hydraulics). I can then investigate (the backhoe is fixed via the hydraulic cover).

So, not sure again what it can be. I reiterate, I'm pretty confident I have the controls in the correct position as I switch between them all every time I use it, pretty much.

I'll keep this posted with updates, and hopefully the final solution.

G'Day Andrew.

Sounds to this bunch of enthusiasts - especially me - like a very interesting machine, particularly with the attachments you have for it. How would you like to post some pics for us? We're quite fond of our classics, and in some cases quite surprised at what can be achieved with them. I reckon the more threads you read ... the more you'll want to read!
To your tractor's problem: Does it suddenly, or gradually stop?
I'm wondering if you've got the same problem I encountered in my 135. Working on steep slopes would stir up the built-up sludge on the bottom of the transmission casing and mix it into the oil. The tractor has only the basic 3PL hydraulic system, and after working for some time would gradually take longer to raise up to 45 seconds - to the point where I switched off for a break, only to find it worked well after a brief time shut down.
I investigated and found the filter on the pump pick-up clogged. Drained the oil, renewed the filter *see footnotes*, washed out casing and refilled with clean oil - been working well for 5 years.
*Footnotes*
1. Filter is accessible by draining gearbox at rear drain plug (expect about 20-22 litres), reach in and unclip filter retaining wire to renew.
2. I believe filter part number and retaining clip design depend on which series of pump is fitted to tractor.
3. Filter is washable and re-useable, although new one is not costly.

BTW, Best Wishes for Christmas and the New Year to all and their loved ones. :thumbsup: