Three point hitch not raising

Scott in ME · Mar 23, 2020

Hi - I have a Bolens/Iseki G154. The three point hitch won't raise. I realize this is a vague problem to diagnose online so I'll give as much info as possible. I posted on this forum when the hitch wouldn't lower, and I was smartly told to turn the valve the governs the speed at which it lowers. I did that and it worked fine. After working fine for some time, it now it works intermittently and sometimes not at all. I didn't realize the problem until I used my first implement, a snow blower. I have left the hitch lever in the "raise" position at all times, hoping that it might actually raise. On a few occasions, it did raise when I was lowering the loader. I used a jack to raise the implement and ratchet tie it in the raised position so I could move the tractor. It stayed up afterwards until I moved the control lever to the lower position. Hydraulics otherwise work fine. No leaks, bad sounds, or anything like that. Is this enough information for someone to give a rough idea of where I might start looking for problems? All input is appreciated. Thank you.

Scott

seville009 · Mar 23, 2020

I would check the hydraulic fluid level (if you haven’t already done so)

Scott in ME · Mar 24, 2020

Hydraulic fluid level is fine. I was just using the tractor and have a few ideas. I've turned a wrench or two but know little to nothing about hydraulics. The transmission and hydraulic system share fluid. There are two pistons controlling bucket tilt. Neither is leaking, but the bucket will not stay all the way up unless I keep my hand on the lever in the correct position. This is getting worse, and the bucket refused to tilt up a few times (Had to lower the loader until the bucket hit the ground, and then reverse). Once the bucket was nudged this way, it tiled up again. Likewise, the hitch raising ability was sporadic, and now functions not at all. The only hydraulic components that work all the time are the two larger pistons that raise the loader. Does this sound like a failing hydraulic pump? I've changed the fluid twice.

seville009 · Mar 24, 2020

Possible that the pump is failing

Did you have the problems before you did the fluid changes? If not, could the filter(s) possibly be bad (clogged or restricting flow)?

Scott in ME · Mar 24, 2020

seville009 said:
Possible that the pump is failing

Did you have the problems before you did the fluid changes? If not, could the filter(s) possibly be bad (clogged or restricting flow)?

Yes, but they are getting worse. There's no external filter. The previous owner didn't knw much about the tractor, but told me a bunch of times to check a filtering screen in one of the return lines. I took the pipe off the tractor where he indicated, but there was no screen there. I can't find a filter screen anywhere, and the service manual I have is almost useless.

kthompson · Mar 25, 2020

If the control valve is working releasing the lever should hold the cyl in place. Now there could also be internal leak in the cyl.

Did not see any mention on the steering but the tractor does not have hyd steering doe it? If it does, will it also give issues like this?
It sounds like you have water or air getting in your hyd oil. Either can turn the hyd oil a brown color. When you changed the oil if water you could have seen it if the tractor had sat for a day or two before draining the oil as water should have come out first. Either water or air will affect the the tractor the hotter it gets as the water can begin to turn to steam and steam nor pure air are solid like a fluid is in compression. If you let it set for a day or two and operates decent when you first begin but steady gets worse to point would first suspect you have a rain water leak or air leak on suction side of the hyd pump lines.

Forget test: if doing this worse as tractor heats up when oil is hot being very careful drain say a quart of oil and let it stand in clear container over night. Water will begin to settle down and with either the color of the oil will turn more back to normal color. The oil mixed with either will have a foam type look due to the little air bubbles in it.

Scott in ME · Mar 29, 2020

I used the tractor yesterday and the three point hitch wouldn't budge when I started it. No chance to warm up. With the control lever in the "raise" position, I can move the lifting arms with no resistance whatsoever (besides that created by their weight). Same thing in all positions of the lever. The manual shows a bleed screw by the hitch's piston, but my tractor doesn't have one. There is no power steering. See photos below. The one with my grimy finger shows there the hydraulic screen is supposed to be. The second photo shows that there's no screen in there. Third photo shows some of the hydraulic/transmission oil I drained out. This fluid hadn't been in the tractor very long. Just because I'm still wondering if these two are related - the loader still lifts just fine. There are two bucket tilt cylinders. When the bucket is tilted down (cylinders extended), it can still lift the front of the tractor. Regardless of this, the bucket is extremely slow to move when elevated, if it moves at all. This also happens when the tractor is first started, as well as when it has been used for a while - no difference. I'm really baffled here.

Leejohn · Mar 29, 2020

2nd picture, what is that is down in there? What am I seeing in there?

Scott in ME · Mar 30, 2020

Leejohn said:
2nd picture, what is that is down in there? What am I seeing in there?

If you look at the first picture, my finger is pointing to a bolt head. Remove that bolt, and the hard line lifts up. Yo're looking down the hole after that line is moved out of the way. I believe it's a return line. The filter screen is supposed to be there from what I've read and what the previous owner told me. There's no screen there.