Hydraulics

[Pilotgmb]

Hello all first time poster here!
I purchased a partially restored dexta in January from a fellow who was not that familiar with tractors. I myself am even less familiar and this is my first ever tractor!
When i picked up tractor the fellow was not even able to show me what and where each control lever operated.
So i go it home and poceeded to learn by trial and error.
When i got it running the front loader operated corectly up down and tilt of the bucket. I was happy!
I then wanted to see how 3 pt hitch worked.
I moved lever up and down and noththing. I then found the diverter/flow control valve just below seat. It was in the pulled out position so i pushed it in and the 3 pt hitch would now waork corectly! I of course had no loader control so i pulled lever back to the out position expecting the loader to work.l
Nothing! Being january and very cold i thought i best leave it till spring and parked tractor with lever in out position.
Today i started it up and after siting loader worked as it should.
So i decided to try 3 pt hitch i pushed lever in and hitch worked. Pulled it back out and again have no hydraulics going to bucket.
Please help i am a auto mechenaic by trade bull have not played with tractors or hydraulics any sugestions?
I have not checked oil level in diff yet but i expect it will be fine as there were no signs of pump cavitation and all hydraulics worked smoothly. Any help or sugestions would be great thank you

[Emiel]

Hi,

The hydraulic system is quite complexed when you're not familiar with tractors.

The 3 point hitch has 2 ways of working;
1st being draft control, qualitrol in Ford language, the 2nd being postion control. You switch between these with the small cast lever below the seat on the right hand side of the casting.

Draft control means that the lift system automatically keeps the amount of draft required to the pre set amount. This amount is set with the big lift lever in the quadrant. For in ground going implemnets like a plough, the amount of draft is measured by the amount of push on the top link. This brillian system is invented by Ferguson and has been in Ford tractors since 1939.

In postion control the position of the two lower lift arms is controlled by the lever in the quadrant, the higher the lever, the higer the arms should lift up. This position is measuryd by a cam follower on a cam which is cast onto the central lever of the lift shaft.

When using external hydraulics for a loader, it is necessary for your safety to use the hydraulic system in draft control mode. With a proper tuned system then you'll have oil pressure with the lift handle to the back, your loader will drop with the lever forward and there should also be a "neutral" position about 1/2 an inch to one inch from the most rearward position of the handle.

When operating in position control the position of the lift arms will influence the control of your loader, wich can lead to accidents.

I advise you to get a owner and a repair manaul for your tractor. These can be googled and downloaded usually. With this you can understand what is working and what is not working and form there we can narrow down your problems. I found these already for you: http://www.smallholderservices.co.uk/si ... hydraulics



On the wiki of this site there is quite an comprehensive manual from Brian on setting up the hydraulics correctly on a Dexta and/or Super Major. This is the one I've used succesfully already many times.

Are you sure there is not a closed valve between your aux service chest and the rams on your loader?

rgds

Emiel

[Pilotgmb]

hi Emiel

Thank you for taking the time with the great reply!
There is what i call a diverter valve under the seat that you can pull out or push in. When i got tractor it was in pulled out position and loader worked great.
I pushed it to the in position and then 3 pt hitch worked up and down as well as the draft part so i was happy
I then pulled control valve out expecting my loade to work as it did originally and nothing loader will go down under its own weight when you push on down stick but wont come up no hydraulic okl going to it.
Any other ideas? I can take a picture of the valve i speak of tonight

[Billy26F5]

To use the loader put the selector lever in the downward position (qualitrol), both the arms and loader should work when the external service valve is in inner and outer positions respectively. If the loader fails then there's a problem somewhere.
Sandy

[Pilotgmb]

Ok so are you saying loader and 3 pt hitch should work at same time? Or are you saying to move 3pt hitch lever to down position then the loader should work?

[Emiel]

Hi,

What Sandy means is this: when the 3pt works with the knob in, the loader should work with the knob pulled out.

Does the lift go up when there is load on the lift arms? Or only without load?

If the lift works as designed then with the knob pulled out the loader should go up. Good chances your problem is in the piping between the aux valve knob and the loader.

[Pilotgmb]

Yes thats exactly where my problem seems to be when i pull knob out there is nothing going through big hydraulic hose to operate loader
When i left knob in out position for the winter the loader worked great this spring until i pushed it in to try 3pt hitch
The 3 pt worked great so i pull knob back out to divert fluid back to loader and now nothing on loader again

[Emiel]

Can you hear the pump working when you try to lift the loader?

[Billy26F5]

Try removing the loader hose and see if it has oil coming out, if it does then the loader will need sorting, if not there is a problem with the hydraulics. Do this by hand, to avoid high pressure oil.
Sandy

[Pilotgmb]

Hello fellas
I found another long lever to the right of seat below the selector valve when i cycle this lever down then pulled it back up my loader hydraulics began to work!
I have printed off most of the service manual but is there a operators manual i can get that points to all the different levers and switches for a newbie like me?
Thank you all who helped me so quickly really appreciate it.

[Emiel]

Hi,

This means your draft control works, and thus the loader with knob pulled out. Then I think your position control linkage is not adjusted right. Probably worn cam follower.

If you want to have it right, it is an easy fix.

Rgds emiel

[Old Hywel]

I’m guessing that you have a separate spool valve block to operate the lift/tilt. This is fed from the external services (knob out).
If you have ‘position control’ selected, and linkage fully up, then there’ll be no flow.
Push in knob and lower linkage slightly, pull out knob and lift main control fully. This should restore flow.
Otherwise use ‘draft control’, again with lever up.
Presumably, while parked up, the linkage crept down by itself.

[Billy26F5]

Always place the selector lever in qualitrol to operate the loader. As for instruction books, they're available by eBay and others (unfortunately no free pdf).
Sandy

[mathias1]

We have a lot of pdf documents on the site. It's under the old ffcn section on the main page

[Billy26F5]

I already looked through that, there is a dutch instruction book there.
There is the repair manual available from another page (I'm only posting the hydraulics section, but they have parts books and repair manuals).
http://www.smallholderservices.co.uk/si ... hydraulics
Sandy