# 1220 NewHolland 3-point lift stopped working



## HangonII (Mar 19, 2016)

I installed a backhoe using the tractor's hydraulic system. It worked fine but when I removed the backhoe, the 3-point hitch lift no longer worked. I would appreciate advice on how to repair the 3-point hitch lift system.


----------



## Fedup (Feb 25, 2014)

Go back and examine the connections involved. It's very possible the oil flow is incorrect, not sending oil to the lift at all, and directly to sump instead.


----------



## HangonII (Mar 19, 2016)

I have a feeling you might be correct. However, I disconnected the line to the 3-point lift and connected it to the output port of the manifold by itself and the lift still did not work. I disconnected the loader entirely when I did this. The loader works correctly so the pump should be good. It looks like the oil is free flowing through the 3-point hitch lift and yet there must be resistance through the relief valve to make the front loader work.


----------



## Fedup (Feb 25, 2014)

I'm only guessing here as to how all this is hooked up. Typically, the loader would be first in line so pressure would always be available there. Beyond that, it's up for grabs. The plumbing to and from the backhoe attachment SHOULD be set up with power beyond in mind, meaning a pressure capable supply to/through the backhoe valve, then returning back into the tractor's system. A third hose for sump return would be expected. It's also possible the return from the backhoe valve may go directly to sump, bypassing the lift entirely since it's not expected to be used during backhoe operation. 
Since you have yet to supply any specifics on your particular arrangement, guesswork is about all that's available.


----------



## HangonII (Mar 19, 2016)

Thanks for the reply. It's more than I expected. I worked on this a good part of the day and came up with the following: It appears that the NH instructions that position 2 on the diverter sends flow to the 3ph lift. I could not make this happen. It may happen with the inlet port attached to the loader. The backhoe has been removed and the tractor returned to it's original piping configuration. Just for information to anyone who wishes to install a backhoe using the tractors hydraulics, this is how I got it to work. I put a tee to the output and went to the backhoe and tied the return from the backhoe to the return on the tractor. I placed a check valve in the supply line to the loader allowing the flow to go just to the loader and a stop valve in the loader line that goes to the inlet to the tractor. With this configuration, the loader worked at all times and the backhoe worked when the stop valve was shut. I also put a 1500psi relief valve in the backhoe line to return to the return. I did this because my backhoe did not have a relief valve. I learn today that the plug at the bottom of the diverter block is where the system relief valve is located. Therefore, the backhoe would not have needed a relief valve. Only problem is that when I try to close the stop valve in the loader inlet line, the hydraulic pump labors like it does not have a relief valve. I could not get the backhoe to work by connecting the return line to the inlet port as instructed by the NH tractor manual. I am still not sure what the inlet port is for. It looks like it's connected to the outlet port.

With all this said, the tractor is in it's original configuration without a backhoe or loader connected to the hydraulic system The diverter valve is set to position 1 and there definitely is flow to the 3ph lift. I attached an air hose at 125psi to the hydraulic inlet of the 3ph and the air gushes out the hydraulic filler port. This should not be with only 125psi of air. There should be a relief valve in there to build up the pressure. So, I guess I have to take the top of the 3ph assembly off to figure out what is happening. Any additional help would be appreciated. Thank


----------



## Fedup (Feb 25, 2014)

You sure went the long way around with all that. I always thought the proper technique was to simply put all valves in series, with three hoses going to the hoe valve from the tractor.With hoe removed, two of the three(pressure supply and pressure return) are connected to each other and oil flows to lift system. 
As for your air check - in theory, if all is correct, air pressure will exit the filler opening when introduced to the T(tank) port on the divertor valve block. With the spool in "loader" position, air introduced to R(pressure return) port should cause the lift to raise(with lever in raise position and no load on lift arms). If the air escapes from the filler with divertor in both positions, you may well have some internal lift/valve issues.


----------

