M4900 Hydraulic Problems. Power steering, PTO are OK. Everything else weak

TheOldHokie

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Apr 6, 2021
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It lift all the way up and down with nothing in it. When you trying to lift a hay bale it won’t even move it
I understand that. It takes a lot more force to lift the bale and you arent getting it. That is a classic symptom of a leaking cylinder.. You need to TEST both cylinders.

Dan
 

ronv23

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M4900 kubota
Apr 4, 2026
43
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Texas
Apply pressure to just the rod side and cap the opposite end. If it extends it is bypassing. Cylinder will be off machine but connected to the hydraulic.
 

TheOldHokie

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L3901/LA525, G2160/RCK60, G2460/RCK60
Apr 6, 2021
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Apply pressure to just the rod side and cap the opposite end. If it extends it is bypassing. Cylinder will be off machine but connected to the hydraulic.
Excellenyt Test both cylinders.

Meanwhile I will do some research. Exactly what model M4900 and loader?

Dan
 

ronv23

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Equipment
M4900 kubota
Apr 4, 2026
43
3
8
Texas
Excellenyt Test both cylinders.

Meanwhile I will do some research. Exactly what model M4900 and loader?

Dan
One cylinder passed the test the other did not. I took it apart and the seal is still there and looks good. I don’t know why it would be bypassing.
 

ronv23

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Equipment
M4900 kubota
Apr 4, 2026
43
3
8
Texas
I put on another cylinder that works and same thing won’t pick up a bale even a wide open
 

TheOldHokie

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L3901/LA525, G2160/RCK60, G2460/RCK60
Apr 6, 2021
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Myersville, MD
windyridgefarm.us
Leave the bale on the loader. Disconnect the quick coupler on the loader valve that goes to the rod end of the cylinders. Remove the female coupler ftom the hose and put the end of the hose in a bucket. Start the tractor and try to lift the bale.

Does the loader go up?
Did you get oil out of the disconnected hose? If yes how much.

Dan
 
Last edited:

ronv23

Member

Equipment
M4900 kubota
Apr 4, 2026
43
3
8
Texas
Leave the bale on the loader. Disconnect the quick coupler on the loader valve that goes to the rod end of the cylinders. Remove the female coupler ftom the hose and put the end of the hose in a bucket. Start the tractor and try to lift the bsle.

Does the loader go up?
Did you get oil out of the disconnected hose? If yes how much.

Dan
Loader did not go up. Maybe 1oz came out if that
 

ronv23

Member

Equipment
M4900 kubota
Apr 4, 2026
43
3
8
Texas
Recoonect all of that.
Disconnect the hose cinnected to the base end of the right cylinder. Put the hose in a bucket and try to raise the loader.

Did you get oil from the hose. If so how much.

Dan
A good stream at an idle will keep coming out if I pull valve
 

ronv23

Member

Equipment
M4900 kubota
Apr 4, 2026
43
3
8
Texas
[/QUOTE]
Yes, nothing comes out when I do not pull the valve for the loader when I pull the valve fluid comes out of the hose