L175 Loader drops tractor

[markchustz]

Have a 1975 L-175 with loader of same age. Had shop replace all seals on the hydraluics two months ago. When i use the loader to lift the tractor's front tires off the ground i can get them 75% up then the loader drops back down.
Only do this to get more traction as i try to back up an incline.
Trying to figure out if the hydro pump is just not putting out enough pressure or if there a relief valve that is opening to keep from overloading the system. Tractor has no extra weight on the front, except the loader. If it is a relief valve, will replacing one i have with a new one help?

 

[Eric McCarthy]

Could be time to do a hydraulic flush and change if you havent done so already.

 

[bruceatlam]

Does your valve have a "float" position? Sounds like your moving past the "lower the loader" position and into a float position.

 

[markchustz]

Have flushed the system. What is float position?? Do 1975 loaders have that?

 

[cmorningstar01]

some loader joysticks have a float position, When you push the lever forward to lower the loader and push past this position it goes into float, Float allows the loader bucket to glide along in the down position without any downward pressure except for the actual weight of the bucket, If you are able to lift the machine with the bucket but as it is lifting it reaches a point that the loader just loses all pressure the relief valve may be activating allowing all pressure to drop, To clarify that this may be what is happening if you push the joystick forward until the bucket starts to lift the machines front end and you just hold the joystick in that position without pushing it into the float position then it could possible be the relief valve.

 

[Eric McCarthy]

I highly doubt he has the float feature on a 1975 Kubota. That's fairly new technology on tractor hydraulics. It could be a problem of having air in the hyd system or could be time for new hyd cylenders all the way around. My dad has an 80's model L275 with a FEL and I cant count the number of times we've had the cylenders repacked and repaird and they still dont work right.