No Hydraulics

Greetings Matthew.

It could be one of a couple of things. You could have a relief valve stuck open, or you could have the hydraulic pump coupling sheared. Have you determined that your pump is actually turning? Of course I wouldn’t expect the seller to own up to something stupid he did, because his scenario wouldn’t have had that effect.

there should be a knob or hand wheel near the seat that controls the amount of falling speed on the three pt. system.  lightly snug it up and back it off a few turns , maybe you will get lucky.

My tractor had this problem and it was a blown pump seal.My mine has 2 pumps one for the steering and one for the hydraulics the hydraulic pump is the rear one on mine.Also the hydraulic reservoir is on the top of the transmission under your seat.

I looked it up and it holds 2.4 gal of hydro fluid with no loader. Just in case you did not know. If you put in a new pump and that tractor I believe is a common sump there is not a lot that can go wrong . If there is fluid over the pick up and it is clean ,and  you verified  that the pump is powered . Have you checked the filter screen , it might be on the outside of the tractor in a tube. As best as I know these systems should be self purging as far as air goes. But look there it should be full of oil.  If not maybe it has to much air in the system and need bleeding  . It kinda takes me back to the pump not working or powered.

As mentioned before, several things could be causing your symptoms.

May i suggest loosening the output fitting on the pump enough that it starts to drip. Then start the engine and observe if there is more flow with the engine running. There should be.

If not, then the pump may not be turning or may be defective. Just because it is new doesn’t mean it works. Then work your way back to the sump. Take the suction line loose from the pump. If the pump is lower than the fluid level it should free flow at least a little fluid.

What viscosity of fluid did you use and what is the temperature there?

In cold weather it takes my Jinma 284 quite a while to warm up enough to lift the 3 point.

Let us know if you have fluid flow at the suction and pressure fittings at the pump.

My Jinma is like piper184 said, 3 pt won’t lift until warmed a bit, but my other hydraulic functions work well when cold.

Is it possible whatever shaft turns your pump is broken. Seems possible if bush hog was stopped suddenly. ( I don’t know if it was running off of this pump, mine runs off of the rear PTO.

If you drained the fluid and rebuilt pump, a few options…. 1. You did wait a bit when engine running, it takes 15 or 20 seconds on mine to fill the FEL cylinders and start them living and quite a few cycles to get rid of the air.

2.  Does your pump have a bypass? My FEL valve came adjusted so low that it did not even lift the bucket. ( I then tightened it up nice so that I then popped HYD lines like candy! After a while I found the sweet spot.) If it has a bypass, did you back it off or not assemble that part quite right?

3. Is there a leak on the inlet side of the pump. That would cause issues.

As someone else mentioned, perhaps loosen the pump outlet a touch and see if there is any increase, problem though is that to increase the preassup for the leak to increase you pretty much have to pressurize ( fill) the whole system.

Another question.

Does the output from your pump go directly to the steering sector at the bottom of the steering wheel shaft?

On my 284 there is a priority valve that is supposed to give the steering system priority over any other hydraulic use. If you have a priority valve and it is stuck or has failed it could be causing you problems.

Does your tractor have rear hydraulic ports? If so you could put a coupler in it and start the tractor to see if there is any oil flow there.

Neither the tractor nor engine parts books for my Jinma 284 show the pump to engine connection details. It is my understanding that the pump has a tang that protrudes from the pump. This tang engages a slot in the drive gear of the engine. I have never had my pump off so I am not sure what it looks like on the inside.

Do you know what engine you have? That might help to find a parts diagram of how things are supposed to be.

Short of that, could you post a picture or two of the pump and pump mounting point taken with the pump removed so we can see what is inside the housing?