Hi everyone, I have a grove tms 375 hydraulic crane and I'm having issues with the outriggers. The four outriggers extend easily when operated, but they won't retract easily. Sometimes the outriggers just get stuck and won't retract when operated. I have serviced all the solenoids and valves controlling the outriggers but it still wouldn't retract. I also checked the hydraulic pressure from the pumps and they seem so high and sufficient to operate the outriggers. I extend the outriggers easily and freely but the outriggers won't retract. I have spent over one month trying to get this fixed but no luck. Please help!!! I need your kind assistance on this.
Change your hydraulic filter.
There should be lock valves on the cylinders, sounds like that may be the problem. And change your hydraulic filter as Knepptune says.
Where are the lock valves located?? I will also change the hydraulic filters.. The sad part of the story is that every part of the crane operates well including the boom, counterweight, swinging turntable etc.. Even the outriggers works fine when it is extended to any length sideways and height.. But it wouldn't retract.. I can't even move the crane from it's current position.. I'm stuck..
I think he's referring to the handles on top of each o/r jack. Basically it's s threaded rod that you screw down by hand and it won't let the o/r jack retract. Should be able to elimate that fairly easy. Turn the handle counter clockwise till it stops then try the o/r. I don't know of any other locks on those o/r's but I could be completely off.
I've seen this before and it was often related to friction between the bottom face of the outrigger beam and the top face of the "tunnel" in which the outrigger beam slides. When the outriggers are difficult to retract have you tried lowering the outrigger jack on each one until the pad just touches the ground, take a hair of weight off the beam and try retracting the outrigger in that condition..? Usually once they start moving you can raise the jack. If the above method works and the outrigger beams retract well then at some point you might have to remove them and clean up/smooth both the bottom of the outrigger beam and also the tunnel it runs in. You may find they are worn or even gouged in some places. Steam clean or pressure wash and get everything absolutely free of grease and (most importantly) dry. Then when reassembling use liberal amounts of dry film graphite lube to get the outrigger beams to extend and retract smoothly. In my experience any oil-based lubricant gets scraped off by the in-out movement of the outrigger beams and ends up on the ground. Make re-lubing with dry film one of your regular PM checklist items. Even after doing all that you may come across the occasional circumstance where it's necessary to take the weight of the outrigger beam with the jack pad to get it to retract smoothly.
I've tried to turn the locks on the outrigger jacks counter clockwise and they still wouldn't retract. The outrigger beams wouldn't retract too.. Both the outrigger beams and jacks can extend but would never extract. I'm confused at this point.
So now you're saying that the outrigger jacks won't go up and also the outrigger beams won't reatract into the chassis, correct..? That's not the impression your original post gave me. I thought it was simply that the outrigger beams that were reluctant to retract into the chassis.
The o/r selector valve controls the extend and retract. If it extends but won't retract it has to be related to that valve or plugged hyd filter. Have you actually checked any pressures. I think those need 1800psi. Remove your hyd oil filter and see what happens. Put the cap back on. Just take the filter out and check wat happens. Usually a plugged hyd filter will affect extend a little and completely shut off retract. Next check your pressure. If it's not filter related it's the in the selector valve. Have you checked voltage at your o/r selector valve?
My thoughts as well Kepptune on the extend / retract selector switch or circuit . Few pages out of the Grove 375 service manual .
Could very well be an electrical problem . As it sounds like everything will extend but not retract .
Thanks.. I’ve tried everything.. i bought new hydraulic pumps and I still get the same results.. the outriggers would extend smoothly, but would not retract without constant revving of the engine.. retracting is too slow..
Retract on those cranes isn't real fast, and it won't retract without increasing engine speed. If you are just idling, neither jacks or beams will retract. It sounds like at first they would not retract at all, now they retract, but its just slow? I don't think it would have been a pump issue anyways, I would think electrical on the directional valve, or in the upper cab at the switch, or at the swivel connections (which have all been mentioned). You could test the electrical by simply jumping 12v directly to the lower solenoids, and the directional, bypassing all your upper electrical, and see if that changes how they function.
Thanks my friend.. I will let you know when it’s done.. much appreciated
Heat and deep creep should do it