Loader Hydraulic problems with FEL & Brush Grapple/3rd Function Valves

[timebak]

I've got an RK37SC and was using my RKT-60 RK T/S brush grapple on the FEL to roll a part of a large tree trunk down a hill to a brush pile that we are going to burn later. I had the grapple jaws open and was using the teeth of the "bucket" part of the grapple, pushing the trunk while lifting the FEL thereby rolling the trunk. I got to the point where there was the stump of a large limb sticking out of the trunk, so I got the teeth of the grapple bucket under the end of the limb stump and curled the bucket back while lifting it and pushing forward to roll the tree trunk.

The bucket only curled back a little, then stopped. I kept lifting and pushing and rolled the trunk down the hill, no problem. When I went to grab another wad of brush, the grapple jaws wouldn't close and the bucket wouldn't curl back but about half of its normal travel. It has no problem moving all the way to the dump position but when curling back, it gets to a point and acts like it has run into a stop.

I checked to make sure there was no mechanical interference or damage to the grapple or FEL. I noticed that if I pushed the button on the joy stick and moved it to close the grapple jaws that the jaws would close a little then stop, but when I move the joystick, with button pushed, to open the jaws, they will not open.

So, does anyone here know how I should proceed to fix this problem? I'm not afraid to tackle this myself.

Thanks in Advance,
Tim

 

[oosik]

First thing I would suggest. Check all the hydraulic connections involved in grapple operations. And not just a visual inspection. Grab the hose and shake/wiggle it aggressively. Possibly some part of your most recent operation snagged a hose and has pulled that connection loose.

 

[timebak]

oosik, Thanks for the good advice. It mirrored what a friend told me. I checked all four of the hydraulic quick-disconnects going to the FEL and the two going from the diverter valve on the FEL to the grapple jaws. I found one of the quick-disconnects on the diverter valve loose and the bottom quick-disconnect going to the FEL loose. They all looked properly secured, and I pulled on all of them, and none came apart. But I decided to disconnect them, one-at-a-time, and clean both sides thoroughly and re-connect them.

As soon as I pulled back the locking collar just a tiny bit on those two quick-disconnects, they popped apart. I cleaned the male and female sides of all six quick-disconnects, first using carb & choke cleaner spray, then wiping everything clean with paper towels, then spraying thoroughly with WD-40, making sure that I got all dirt and debris off of and out of both sides of the disconnects, then put them back together, before moving on to the next one.

After all was clean and re-connected, I fired up the tractor and all worked perfectly. The grapple jaws worked noticeably faster, as did the dump function of the FEL, leading me to believe that those two connectors had been loose for a while.

Thanks again!