zetor 7211 problems

[habbi]

I have a 1984 Zetor 7211 with a few problems.

The high range PTO pops out of gear when blowing snow, the low range (540)
works fine. I assume it is just a matter of turning the splined shaft
between your legs to engage high or low. My manual shows a small metal lever
that should be on the shaft but my tractor only has the small vertical
splined shaft. Actually could you explain this in more detail. Why is there
a splined shaft here.

Also the differential lock is giving me problems. The mechanism used to keep
coming apart but now that I have this fixed it does not seem to work at all.
I have done the proper adjustment according to the service manual and it
worked for a while but sometime it would stay engaged and I would have to
pull up the foot lever with my fingers to disengage it. Now the foot pedal
is loose and stays in the down position ( I can lift it but it just drops
back down) and the differential stay in open mode. How is it designed to
disengage? Is this a sign that something is broken inside the differential?

When it is very cold out (20 F) I cannot turn the tractor to the left, it
will only turn right and it turns easily. After running for a while (1/2
hour + ) it will start to turn to the left. Is this a sign of water in the
cylinder? The fluid in the reservoir looks clean, clear and red.
I went through the service manuals and these problems are not addressed.

Thank you for any help .

 

[markku]

My 7745 do the same. It is because blower do rotate the pto when you are lowering eng. revs. It should not do that when gearbox is getting warm enought (+50 to 60 degrees). Least mine zetor dont do it anymore when it get warm.

Does anyone has idea what kind of gears are in pto connector?

 

[crystalman]

The diff lock should disengage by itself when you are through the slippery patch and you get proper grip.You may have to steer to the left and right to release the load on the diff or stop and reverse if this fails.