Lift bucket problem

[Mike G 1]

Hi I have a 1975 D180 with 550 lift bucket, when I engage my pto bucket goes up and down meanwhile it keeps dumping bucket. If I pull lever to tilt bucket up it’s a fight and will fill up my reservoir? I removed valve from block and cleaned up return spring it’s still dumping I’m thinking it’s something in the valve block? Any help would be appreciated.

[wallfish 18,087]

Any chance you can post some detailed pictures? Like an overall from different angles but close enough to see the hydraulic lines?

If easier you can send them to uremailing@yahoo.com and I'll post them for you.

I'm guessing it's the plumbing of the lines from the valves to the cylinders. Could one or more be crossed?

Is this a new problem? Started after changing anything? Any new parts added? Always been a problem?

 

Are you saying the bucket automatically moves when you engage the PTO to drive the pump? Or just when you move the valve lever?

[8ntruck 7,833]

 Same questions I came up with.

 

to the forum.  I've only been a member since 2019 and I have not seen a problem like this.  Congratulations,  you may have come up with a new problem to solve!  Don't worry, enough good people here that bounce ideas around that I'm pretty sure we can come up with a solution. 

[roadapples 6,983]

[oliver2-44 10,712]

Is the front end loader hydraulic pump driven by the PTO

 

Pictures and some background on the tractor and loader

 

[8ntruck 7,833]

Thought about this while I was walking the dog today.  If the pressure line from the pump got connected between the bucket dump cylinders and the control valve, I think you would see the symptoms you are describing.  However, the pressure hose from the pump is generally connected to the valve manifold, so if it was connected to the wrong place, the lift cylinders would probably not operate correctly.

 

If you have had hoses disconnected lately, go back and make sure they are connected correctly.  Valve manifolds generally have ports labeled 'P', 'T', 'A', and 'B'.  The pressure from the pump goes to 'P'. Return to the resevervoir connects to 'T'.  'A' and 'B' connect to the cylinders.  If you have a pressure line going into an 'A' or 'B' port, things will start to get weird.

 

Disclaimer:  this is just a guess based on your written description and my basic knowledge of hydraulics.  Pictures and a hydraulic circuit diagram for the system are needed for a more accurate diagnosis.

[wallfish 18,087]

5 hours ago, 8ntruck said:

If you have a pressure line going into an 'A' or 'B' port, things will start to get weird.

6 hours ago, 8ntruck said:

Thought about this while I was walking the dog today.

Just curious. Was it intentional or just happens like the proverbial "light bulb in the middle of the night"?

[8ntruck 7,833]

45 minutes ago, wallfish said:

Just curious. Was it intentional or just happens like the proverbial "light bulb in the middle of the night"?

I read this post yesterday, thought about it, then went on to other things.  The subject popped into my mind this morning on our walk.  Not the answer, but a more ordered, more informed thought process that let me come up with a reasonable explanation of what could be wrong.

 

I'd have to say that my mind was working on this in the background overnight.

[Mike G 1]

I’m sorry everyone I’m new to this site and could not find a way to reply. Thanks for all the input, I got frustrated after freeing up the valve block, sealing all connections and it still doing it I removed the front tilt shocks removed snap ring to find both upper o-rings on the shocks dry rotted badly into pieces allowing fluid to pass pushing bucked downward. It was a very simple cheap rebuild and problem fixed. Sorry again I’m still learning this site and how to navigate.

[8ntruck 7,833]

Yup.  Bypassing bad piston seals would do it.  Never ran across that problem, so I didn't think of it.

 

Glad to hear you are back running.