Zetor 6718 Lift not working when warm

[djsumcp20oldleawharfcouk]

Hi,
Zetor 6718 the lift works ok when cold, first started, but once the tractor has been running for a while it does not work. I assume this is because the oil is hot and thinner. Have cleaned the magnetic filter and changed the oil in gearbox but still the same. There is a Lift unit shown in manual I assume is the pump, is this under the cover under seat together with the lift cylinder, will the problem be with these, seals?
Thanks for any advise.
David

 

[diyfarmer]

Hi,
Zetor 6718 the lift works ok when cold, first started, but once the tractor has been running for a while it does not work. I assume this is because the oil is hot and thinner. Have cleaned the magnetic filter and changed the oil in gearbox but still the same. There is a Lift unit shown in manual I assume is the pump, is this under the cover under seat together with the lift cylinder, will the problem be with these, seals?
Thanks for any advise.
David

Under the lift cover there is a cylinder that when the pressure comes on it the oil is getting passed the seals and lift doesn't work but its cold it works ok, but how you would test it put a big weight on it when it's cold and see will it fail as well.