3pt Hydraulic Noise - Kubota B6100 4WD

[ttj49]

The noise is similar to that of a cars power steering noise when it's low on fluid and the wheel is turned all the way.

When I first start up the tractor and the 3pt lift arms are all the way down, the noise is immediate until I lift the arms.

When I slightly pull the lever to to just barely engage the hydraulics and lift the 3pt arms, the noise occurs very loud.

If I pull the lever past the "slight" position the noise disappears until I pull the lever all the way back. When the lever is pulled all the way back, the noise is very loud.

Hydraulics are very strong. Lifts 400+ pounds without problems. Lowers implements without problems. Hydraulic speed adjuster works fine.

Kubota service manual says noise is caused by the Hydraulic Pressure Relief Valve" not being properly "adjusted" which I understand is a spring, some shims and maybe a ball bearing, and kits are available to fix this problem.

Is this correct? Is my noise problem the pressure relief valve? Could there be something clogging the valve, or the hydraulic system?

The manual does not tell me where the pressure relief valve is located. I have attached a photo of the upper portion of the 3pt lift unit.

Thanks in advance for your opinions.

 

[Dwarner]

That is normal for your tractor's 3 point hitch.

 

[hodge]

That is normal. The hydraulic valve isn't progressive, but on or off. You are hearing fluid pass through the partially opened valve. If you pull the valve all the way when you raise the arms, there is no noise, other than we you initally open it. If you feather it, it is very loud.
My B7100 is the same way, and it's been that way for over 900 hours now.

 

[ttj49]

Thanks. I can accept that if that's the way it is. I changed the hydraulic fluid and filled with new Kubota UDT (not super) and cleaned the hydraulic filter with kerosene, and the noise actually got worse. Before I changed the fluid, the noise would only occur when I first started the tractor when the lift arms were all the way down, it squalled until I lifted the arms. Now it squalls when I pull back on the lever. It didn't do that before I changed the fluid and cleaned the filter. The fluid capacity is right on the money......