I have an 85 M4050 and the lift arms are stuck in the lowest position after being parked with lift all the way down. draft control does not appear to be engaged. Changed fluid and cleaned filter a few weeks back, all looked good. Fired right up and lift worked as it always has. Did some bush hogging and parked for a few weeks. Fired it up yesterday and the lift arms will not raise. I still have the bush hog attached, if I back uphill with position lever up the arms are forced up by the bush hog and stay up as high as the bush hog pushes them. Arms will lower if I lower the position lever but will not raise. Any trouble shooting options or idea why it would suddenly lose lift? Maybe linkage issue or stuck valve? My wallet hopes it is not a pump issue. It has never had any hydraulic issues in the past. Thanks in advance!
Kubota M4050 hydraulic / lift arm problem
- Thread starter AlabamaRed
- Start date
Do you have any other hydraulics on your tractor like rear remotes or a loader?
The easiest condition to rule out is a pump sucking air because of a deteriorated piece of rubber hose on the suction line for the main pump.
A brittle cracked hose will not leak oil out but will allow air to enter and then you have no pressure.
Dave
I noticed a small fluid leak at the filter. Bad oring on the cover at bottom of filter. Replaced oring and short hydraulic hose and clamps upstream of filter. I cracked the suction line on top of the pump. and poured some fluid in to prime, and reattached. Ran the engine, still no lift after a few minutes. Shut off and checked for leaks, none visible.
Next, I tried cracking the high pressure line with engine runnjng. Cracked the line line shut it off after about a minute., no fluid ever came out other than a few drops.
I Noticed that the hydraulic pump was a good bit warmer than power steering pump. I ran out of ideas and did not want to risk the damage to the pump so I called it quits for the day.
I am starting to believe the pump may be shot. Any other ideas before I pull the pump and start thinking about shelling out for a replacement?
h
kubotafreak
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Any other hydraulic parts like a loader? These are before the 3point in priority.
You didn’t say if the power steering worked or not. Same supply if it’s a tandem pump. If the pump is hot and no fluid comes out the smaller hard high pressure line. You have a supply issue. The fluid cools the pump.
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what was your solution to this problem, my 3PT wont raise after oil change and i have done debug like yours but still no lift , this was working before hydraulic oil change, one more thing i noticed is that
the power steering works for me but makes a weird noise and goes tough sometimes , otherwise when tractor is running it seems to be ok. but when i use the 3PT levers i hear no sound nothing
North Idaho Wolfman
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Hi Wolfman Thanks for quick reply , i tried turning it back and forth many times with revving the engine
but still there is no lift , do i i have keep turning it until i stop hearing the weird sound from the power steering pump ? It seems to be very difficult to turn as well looks like its like struggling.
North Idaho Wolfman
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Leave it at an idle, and yes turn it back and forth till it quits whining, also moving the three point lever while turning the wheel.
Also double check the fluid level.
Also double check the fluid level.
Thanks for all the cues , i will do the same tomorrow will report back , oil level checked today , was slightly lesser than max.
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Just went and looked up the schematic for the hydraulics on your M4500.
I'm wrong about using the steering to burp the three point, your steering is on a completely separate hydraulic tank under the hood.
Have you checked that level?
If it's low then that would explain your steering issues.
As far as the three point operation, you'll need to move the control for that unless you have a loader attached or you have remotes to help bleed it.
This happens more and more on older units, it's the pump not getting suction and a prime.
Are you 1005 sure you got the filter in properly and sealed up?
One other option is to crack a high pressure (small line) on the main section of the hydraulic pump.
I'm wrong about using the steering to burp the three point, your steering is on a completely separate hydraulic tank under the hood.
Have you checked that level?
If it's low then that would explain your steering issues.
As far as the three point operation, you'll need to move the control for that unless you have a loader attached or you have remotes to help bleed it.
This happens more and more on older units, it's the pump not getting suction and a prime.
Are you 1005 sure you got the filter in properly and sealed up?
One other option is to crack a high pressure (small line) on the main section of the hydraulic pump.
Thanks for this clarification, actually I will double check the filter tomorrow as that was one of the first things I cleaned and now don't remember if I did a good job seating it back properly, I tried the backing up and keeping transmission higher than pump method and cracked the inlet but it didn't help, there is an auxiliary hydraulic lever under the seat for my tractor I don't know what would be the process to use that to bleed the line.