tractorguy2
Well-known Member
I posted earlier about a hydraulic problem with a 621.The previous owner had the hyd pump rebuilt and gave up when it wouldn't work correctly.
The problem was the 3pt would lift very slow and do a lot of shaking while going up. I had several people suggest the unloading valve was sticking. Today dad though I should try bleeding the system again. He suggested using a clear rubber hose connected to where the bleeder goes in the pump and running the oil back into the sump through the filler plug under the seat.
We could clearly see the air bubbles in the clear hose. The tractor ran about five-eight minutes before all the air bubbles disappeared from the inside of the clear hose.
The 3pt then worked correctly. Raised quickly and smoothly.
We then let the tractor sit for about three hours and started it again. It was full of air again. It must either have a bad o-ring or the rebuilt pump has a bad seal.
The current owner bought it to resell. He offered it to me for $1600. It might get cheaper if I have to split it or redo the rebuild on the hyd pump.
The problem was the 3pt would lift very slow and do a lot of shaking while going up. I had several people suggest the unloading valve was sticking. Today dad though I should try bleeding the system again. He suggested using a clear rubber hose connected to where the bleeder goes in the pump and running the oil back into the sump through the filler plug under the seat.
We could clearly see the air bubbles in the clear hose. The tractor ran about five-eight minutes before all the air bubbles disappeared from the inside of the clear hose.
The 3pt then worked correctly. Raised quickly and smoothly.
We then let the tractor sit for about three hours and started it again. It was full of air again. It must either have a bad o-ring or the rebuilt pump has a bad seal.
The current owner bought it to resell. He offered it to me for $1600. It might get cheaper if I have to split it or redo the rebuild on the hyd pump.
