How can I test a loader for cylinder vs control valve leakage??

[4lane]

I have a Kioti CK30 with a KL130 loader. My loader is leaking down pretty rapidly. When I raise the loader it sinks down over the course of a couple hours. The FEL will raise the front tires slowly and the tractor immediately (slowly) returns back to the ground within a minute. I'd like to determine whether the issue is a leaky cylinder or the control valve.

• Can I raise the loader, turn off the tractor, and disconnect the couplers nearest the loader joystick? I'm thinking if the loader drops it's the cylinders and if not it's the valve??
• If it is the valve, could I then swap the up/down couplers and see if it doesn't drop to ID which spool needs replacing?

Any other suggestions/ideas? Thanks!

 

[ptsg]

That's exactly what you should do to diagnose the problem.

Since you said it drops down quite fast, I would go with leaky cylinders. But test it out and let us know.

 

[4lane]

That's exactly what you should do to diagnose the problem.

Since you said it drops down quite fast, I would go with leaky cylinders. But test it out and let us know.

Great thanks. Are there any precautions I should take when disconnecting and reconnecting (considering hydraulic fluid under pressure)? If I disconnect under pressure, should I expect fluid to come out of the coupler(s) if it leaks past the cylinder? And reconnection is simple?

 

[ptsg]

Just don't lift the loader too high. Just enough to check if it will drop or not. You don't want it to just fall on the ground if the problem is in the cylinders.

Also, wrap a rag around the coupler while disconnecting, it will disperse any pressure plus it will catch most of the oil that will come out.

If the problem is the cylinders, it will leak internally, so you won't much more oil in the coupler than you do while removing the loader from the tractor.

 

[4lane]

Thanks much. It will take me some time to get to this but once I do, I'll give it a try and will report back.

 

[oldnslo]

I presume you are talking about the loader lift cylinders and not curl cylinders.

For the loader cylinders to drift down or retract their is either an external leak or the directional valve is leaking.

Bad piston seals can contribute to the valve leakage since you now have both sides of the cylinder under pressure from the load so you now have two leak paths through the valve Vs the normal one path.

Do you have some way of supporting the loader a ways off the ground? If yes raise the loader, support it, unplug quick disconnect in the cap end of the cylinders. Remove the support, does the loader drift down? If yes you have bad seals on one or both of lift cylinders.

If no your valve is the source of the leak.

 

[Leejohn]

If there is pressure on the system you can not hook or unhook them. Use a floor jack to hold loader up then you can get the pressure off then unhook, then let jack down. Use the jack to hook back up.

 

[4lane]

I presume you are talking about the loader lift cylinders and not curl cylinders.

For the loader cylinders to drift down or retract their is either an external leak or the directional valve is leaking.

Bad piston seals can contribute to the valve leakage since you now have both sides of the cylinder under pressure from the load so you now have two leak paths through the valve Vs the normal one path.

Do you have some way of supporting the loader a ways off the ground? If yes raise the loader, support it, unplug quick disconnect in the cap end of the cylinders. Remove the support, does the loader drift down? If yes you have bad seals on one or both of lift cylinders.

If no your valve is the source of the leak.

Yes, I can support the FEL with a jack, then remove it.

What do mean by ç*¥nplug quick disconnect in the cap end of the cylinders?

 

[Dave M7040]

Many owners with cylinder issues have found this test procedure very helpful.

Dave M7040

 

[Groo]

If the valve did not leak a drop, you could drill holes in the piston, and the FEL wouldn't drop. Total cylinder volume changes when the cylinder moves. The valve is leaking.