Hydraulic lift hicups

[WillieLandini]

I have an Mc cormick International 434. The hydraulic lift has hicups and lowers by itself when tractor is not running. Unless I close the valve on the front of the lift cover then the lift stay up. Anny idea where I can start looking for problem pleas?

 

[DLTTrekkers]

Will help u .

 

[DLTTrekkers]

 

[DLTTrekkers]

see at top right ...thats where that piston with the small spring going in....you need to make a punch to remove that to replace all those o-rings ....some outside and one in one off those valvespacers

 

[DLTTrekkers]

messure the tip protruding from the casing to reinstall to the same lenth

 

[DLTTrekkers]

 

[DLTTrekkers]

Now uyou can see all the valves in that hydraulics. The o- rings I am talking is on the inside of number 15

 

[DLTTrekkers]

 

[DLTTrekkers]

 

[DLTTrekkers]

non-return valve is no 7

 

[DLTTrekkers]

relieve valve is no 10

 

[WillieLandini]

I have found some problems on the lowering spool and seat is worn so I wil get it fixed so it can seat corectly. And I will also replace all orings on lowering spool. Thanks for all the help and support DLTTrekkers

 

[WillieLandini]

Looking for lowering spool and spool seat part number 3049 142 R93 if anny one can help pleas

 

[WillieLandini]

Now I have the lowering spool and seat fixed I polished the seat and spool with bit of grinding with a soft grinding stone. I got everything back and in and put lift back but stil same problem. With all new orings and spool and seat fixed.

 

[DLTTrekkers]

Then you must look for a buildin problem !

 

[WillieLandini]

I have found the problem the copper washer behind the seat of the non return valve had a litle crack in it looks fine when looking at it but I took a torch and put a litle heat to it and there it was a small crack. Replaced the washer and now my lift is working fine.

 

[WillieLandini]

Thanks for all the help.

 

[DLTTrekkers]

Gr8 !