Kubota loader control too sensitive

[Arky217]

Hello all,

I have a Kubota L4200 with loader.
Every time I use the loader to do something somewhat delicate,
it seems to be too sensitive.

In other words, say I want to lift something or lower something slowly,
it seems that I keep moving the control lever and then suddenly the
loader jerks up, or if I'm lowering, it crashes down. There seems to
be no gradualness (if that's a word) to the control.

I do have a couple of 0.060 orifice restrictors that are suppose to be
for a Kubota (I can't remember where I got them), but I have no idea
where to install them.

Do you think that they would soften the control somewhat ?

If so, where should I install them. Possibly the inputs to the control valve ?

 

[Fallon]

Idle down for smoother control, get better technique, or replace the valve. Restrictors are fine for smaller cylinders (I have them on my TnT), but are going to make loader controls painfully slow to operate.

If you put restrictions on the input or outlet if a open center hydraulic system either you'll blow up your hydraulic system or overheat things in a few minutes. If its upstream of the pressure relief either a hose or the pump itself will blow up. If it's on the power beyond the pump will continuously force fluid over the relief valve turning your hydraulic system into a 10hp heater. Things will melt and/or catch fire pretty quick.

 

[Code54]

Is this a new machine or new to you. Normally all the Kubota I have and have driven are extremely smooth and precise. I am thinking something is actually wrong with he machine. I can lower a 1000lbs implement onto the trailer with the front end loader without any bump or bang, smooth as silk with my current Kubota (and even all past ones we're the same).

 

[Peter 315]

Did you spray the loader control valve linkage with oil , Maybe its binding up causing it to be jerky............

 

[jeff9366]

Has the Loader always been sensitive or only sensitive after a hydraulic fluid change?

There are considerable variations between hydraulic fluids.

 

[Arky217]

Thanks all for the replies.
I think the L4200 is a 1998 model.
It had 700 hours on it when I got it about 8 years ago.
It's got 800 hours on it now and yes, it was sensitive when I got it.
I changed the hydraulic oil when I got it, but that didn't affect the control.
If I go REAL SLOW with the control lever, I can control it better, but
it seems there is a point where it does nothing then a hair more it is full blast.
This is especially true on the bucket tilt but also on the lift as well.

I guess I'll just forget about the restrictors, sure don't want to damage the hydraulics.

 

[DMW]

Have you checked the condition of the springs on ends of the valve spools?
Try this thread to inspect the lever:
https://www.tractorbynet.com/forums/kubota-owning-operating/411085-la680.html

 

[Tx Jim]

I had FEL boom lowering control problem on my Kubota M4900 several yrs back. Boom lowered to abruptly when handling 1000# rd bales. I installed and adjustable flow control valve similar to valve in photo in boom hyd circuit & that solved my control problem.

 

[Grandad4]

What he said. It is not right for it to be abrupt like that. On an old tractor like that you one-by-one work you way down the list of possible causes. I'd start with mechanical issues. Damage to frame or pins, etc. Then hydraulics. Loader control a prime suspect.