Zetor 6745 hydraulics questions

[brian_mac]

Gday All
Hydraulics have stopped working completely after running low on gearbox oil.
Is there another oil filter inside or just the magnetic one on top?
I guess the hydraulic pump is attached to the plate under the back end,anything special to do before pulling this off for a look?
Any other suggestions?
Thanks
Brian

 

[Renze]

i was going to say there is an aluminium plug on the bottom of the pump plate with the filter on it, but i think thats the later series, the 7 series had the filter on top of the 3pt lift cover....

 

[askinner]

Hi Brian,

Assumuing the hyd pump is in gear (left lever between your legs all the way forward, and little lever right in the centre either facing left or right), and the oil level is ok, I would suggest that maybe the relief valve is stuck open, or the hydraulic pump has been damaged from running dry. Both are mounted to the plate you refer to in your post. The suction screen for the pump is mounted to the pump also, they often clog up.

The relief valve simply unscrews off banjo fitting it passes though, and the body of it unscrews apart (after cutting the lockwire if it's still there). There is only a needle, spring, and some shims inside it, make sure you don't drop the shims.
As far as checking the pump, you could either dismantle it, or you could fill the suction side with oil and turn it over by hand whilst blocking the delivery side, it should push your finger off the port, if it leaks from the little leakage holes in the end of the pump rather than pushing your finger off, throw the pump over your shoulder!

Cheers,
Aaron

 

[brian_mac]

Thanks I've taken out the pump and cleaned all the sludge out.The filter was completely clogged.Zetors seem to survive no maintainance. I'll fill the oil and try it.

 

[brian_mac]

All working better than ever. I'm amazed at the neglect these tractors can handle.Thanks for the help

 

[agostonius]

Hi all,
could you please tell me under which rear plate is the hydraulic pump fixed to? perhaps a couple of photos would be of use. I am having hydraulic problems with my Zetor 6745. At sometimes the 3 point lifting isn't working. It doesn't lift. Oil level is ok, oil pump is in gear, and I don't know where to look at hydraulic pump or suction valve if it isn't clogged up.
thanks

 

[Renze]

On the bottom of the rear axle housing. Park the tractor nose down into a ditch so the oil doesnt run out while you take the bottom cover off from underneath.