02-12-2013, 09:39 PM
Case 590 SL backhoe/loader outriggers weep down slowly after retraction. When in down position machine drops down til rear tires are grounded. Both work strong just don't hold. Any help would be appreciated, and thanks in advance.
02-13-2013, 04:40 AM
Some reading material, not model specific...Hydraulics are hydraulics different components are used but similar, may give you an idea where to start:
02-13-2013, 06:01 PM
I made a couple tests and it seems both outriggers drop down when not in use and both want hold machine up.
02-13-2013, 07:34 PM
Have you checked all the hose connection to see if that's where the oil is going ? How many hours on the back hoe? what condition are the stabilizer rods in ? if you have dents or marking on the rods or heavy wear in the seals then rebuilding may be in order.
02-13-2013, 10:50 PM
With no sign of exterior leakage when the cylinders relax, the valves are the prime candidates. Even with no piston packing, cylinders will not relax if the oil can't get out.
02-15-2013, 06:40 PM
I just bought this hoe a 95 year with 6200 hours. I washed around stabilizer fittings enter the valves block (what's it called no manuals yet) and although I do have some clear oil drops on another fitting it looks like stabilizer fitting are good with no overt leaking. I cycled the legs 10 times after cleaning and they still don't hold. One drops the wheel to ground in about 15 seconds. I would conclude the stabilizers don't hold 15 sec with little to no leak.
02-15-2013, 11:58 PM
try some lucas hydraulic booster heres the link
02-16-2013, 02:19 AM
I wonder if the hydraulic relief valve might be leaking allowing oil to return to the hydro tank since you say you don't find any external leaking , the stabilizers should not act the way you have noted .
02-16-2013, 05:34 AM
The relief valve deals with overpressure only. Once a valve is centered, the cylinder is on the wrong side for the relief valve to have any effect whatsoever on it.
The valve body or spools are worn. With no exterior sign of leakage, the leakage has to be internal, and that is through the valves.
02-18-2013, 07:45 PM
I drained all hydraulic fluid from reservoir and discovered glass fluid level indicator was incorrect, cleaned and reinstalled. Pulled about 10 gallons out, was a lightly brownish color but nearly clear on fingers. I poured 5 gallons new fluid and about 3 gallons of Lucas booster chainsawearl recommended. Ran a few cycles but got dark. I'll run some more cycles and see if things tighten up. I've also noticed the right hoe arm swing around is fading a little if machine is tilted downhill to that side. Man!