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Grove RT528 Crane

giordanoalfie

New Member
Joined
Aug 15, 2018
Messages
2
Location
33619
Hey, how do you get the Boom Down on a Grove RT528 Crane with a Bad Computer? I need to transport it to a repair shop but the Boom is too high.
 

crane operator

Senior Member
Joined
Mar 27, 2009
Messages
8,777
Location
sw missouri
Depends on what computer system is in it, and what computer you are having trouble with.

If its a PAT style computer and the Lmi is the problem, you should be able to go to the 1' x 2' box back on the counterweight and there's a key on the bottom of it that you can turn and it overrides all A2b functions. If that key doesn't work (they tend to get moisture corroded), you can put 12v there, and if that doesn't work, run 12v jumper wires to the shut off coils on the pilot lines. Pilot line coils are generally under the boom between the uprights holding the heel pin.

All this is assuming its not a engine computer that you're talking about in a newer 528. If you are having engine troubles and need to get the boom down (engine won't run), I would grab the tip of the crane with another crane, pull the holding valve on the boom cylinder, and slowly let it down. Holding valve will be in the square block on the boom cylinder, looks like a little round cartridge screwed in there. Oil is going to go everywhere, so be prepared.

grove-rt528c,977223-1.jpg


The box with the key switch is right on the front of the counterweight, sticking out the bottom of the box. If it won't turn and/or the key is gone, you can just open up the box and jumper it in there.
 

giordanoalfie

New Member
Joined
Aug 15, 2018
Messages
2
Location
33619
Good Morning, it is the Boom Computer that is Bad. It's the type that sets on top of the dash. I don't know the year, it's not a newer one. The serial # 76749 RT528C. The engine Is running, the outriggers are Not Functioning too. So the Boom needs to come Down and the Outriggers back in. Thank You for helping.
 

crane operator

Senior Member
Joined
Mar 27, 2009
Messages
8,777
Location
sw missouri
I'm wondering if you don't just have a 12v problem if you have no computer and no outriggers. The computer is not linked at all to the outriggers, however if you don't have 12v you aren't running outriggers or boom or winch. Do any functions work?

The outrigger solenoids are down underneath front and rear, but to jumper wire that stuff, you will also need to run the directional control, its probably right by the swivel in the lower mounted to the lower frame of the crane.

You can pull holding valves on the outriggers, and push them up. You can also pull hoses on the beams and push them in, here again, oil is going to go everywhere.

If it was me, I'd do a little 12v investigating and see what the problem is before breaking a bunch of hoses loose.

The best pat computer guy (that's what factory lmi is, I don't know what's in yours without a picture) is Bob Basil of Basil Crane repair. He sells parts and has manuals for the PAT systems if you don't.
 

crane operator

Senior Member
Joined
Mar 27, 2009
Messages
8,777
Location
sw missouri
Post up a picture of the swing gearbox. Most are spring applied, with hydraulic release.

You may need to get a gauge on it and check the pressure- they are really sensitive. Or the seals are out of the piston that the hyd. pushes to release it. If I pull the brake pack apart to look at it, it gets new seals when it goes back together.
 
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