Hydraulics Bleeding By?

robertm · Jan 6, 2003

Needed a little more space in the barn the other day, so I raised the LA272 loader on my B7500 Kubota. Went out to the barn two days later, and the bucket was on the floor! /w3tcompact/icons/shocked.gif Whew! Glad the hood of my Shaguar (really an F-250) was not under it! /w3tcompact/icons/laugh.gif Anyone had this problem before? The dealer says it will always happen, unless I disconnect one of the hoses from the loader control valve. I can't believe it. Is this somehow related to the hydrostatic models only? Help!

herbenus · Jan 6, 2003

On my 4200, the loader will bleed down. But for safety sake (kids at my house), I never leave loader up unless I'm right there loading branches in or something. It's always down when parked.

jrlichina · Jan 6, 2003

Yes this will always happen without regard to the type of transmission. The control valve has a certain amount of leakage built in which is used to allow the valve to move and to lubricate the spool itself. Hydraulic cylinders can also have some internal leakage. If the O-rings are worn or there is internal damage to the cylinder surface you can experience leakage. The rate at which your loader will bleed down depends on your control valve tolerances and the amount of leakage in the cylinders. Bottom line is you most likely don't have a problem if the loader works like it should. In general for safety reasons you should lower it when not in use.

rdbrumfield · Jan 6, 2003

As with all hydraulics, gravity wins. Sooner or later they are all on the ground. As the cylinders wear the oil gets around the packing to the other side of the cyl. Haven't seen a rig yet that didn't, even from new, just takes a bit longer.

Anonymous Poster · Jan 6, 2003

I read somewhere about the manufacturers allowable bleed down rates on loaders and backhoes. I can't remember the figures but they were much higher than I would have thought. This is very normal and gets a bit worse with more use.