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580C boom fall at Unlock….

KevinK2 ยท 2012-04-29 17:47

Gotta pick the minds here in HEF again...I have an '80 CK, C model w/extend-a-hoe. The boom won't lift high enough to even begin engaging the travel lock. I have to roll out the bucket and push the boom up with the extendahoe until I can hit the boom-down to grab the lock. When I release the boom, I can push the pressure off the lever, and then ease it down until it gets to that (i'll call it slack, or sag in the cylinder pressure) point and then it free-falls until the pressure builds (about 2-3 ft at the top of the boom) and bounces in the cylinder while it bucks the machine at bit. definately seems like air in the hydraulics, but I would have thought it would purge that out after cycling a few times. It's dangerous at best, but it can't be godd over time jerking the machine around so much. Any knowledge? symptoms? cures?

Replies14
  1. #1Deere500a2012-04-29 18:31

    That sounds normal for a Case they don't boom all the way up. When you boom up at the last second throw the lever the other way (down) it will kick it that last foot to lock the boom, out riggers and speed help. Last year helping a nieghbor run his 680 Case I was cleaning out the bed of his Pickup, I reached out bringing the bucket to me booming up, I hit the end of the bed and ripped the tailgate off because the boom just dropped a foot. I forgot about that, Deeres will boom all the way up. Case hasn't changed that style even the new ones will boom up about 2/3 the way and go limp.

  2. #2Deon2012-04-29 18:34

    I don't run a Case but it sounds like you may be new with the Case backhoe. I think you have an overcentre boom. If so, you need to pull up on the control and just at the right time, quickly shift your contol to the down possition to cause the boom to jerk forward and reach the lock possition. Its strang I know but its a Case thing.

  3. #3KevinK22012-04-29 18:47

    I'll have to video the thing in action - even when i tboom up, I know of the reverse "pop" for the lock, but it won't get high enough to do thatMight be some scoring in the last few inches of one (or both?) boom cylinders. They don't leak out, but, like most tires seals, they do bleed down....It's more that bounce on release that concerns me, but if it's noraml, well, that's that I suppose....more to come!

  4. #4GWS2012-04-30 15:45

    My 580C does the same thing. I get around it by running the extendahoe down to support the boom. Then start lowering the boom and pulling up the extendahoe at the same time. First time I let it go over on it's own I thought it would blow out the boom seals.

  5. #5Bill Smith2012-05-01 07:04

    Yup it is a Case thing . Rev her up on the RPMS . Boom should be at least half way down , pull hard on the stick / as soon as it gets to the point it does not want to come to the end push the same stick forward . This is the harsh way to do it but as time goes on all it will be is as much as a click .

  6. #6dwloop2012-05-01 08:32

    Kevin, X2 what Bill said. The manual states to have the stabilizers down and the throttle about half. I have found that it works better if the front of the tractor is down a little. The stabs down keeps the bounce at a minimum. Just takes timing and hand-eye coordination, get the boom coming up with some momentum, and when it gets to the top a quick snap in the opposite direction to get it to click in to place... When letting it back down it will bounce some, I get mine out of the lock and let the boom down a little to relieve the pressure. It is a Case thing, the C's and D's I ran years ago did the same when new, and the Super M I was renting last year did also. BTW: I had some really old hoses on mine at first, this was not what popped them.... Its those stumps!! I don't believe it is as hard on hoses and seals as roading without in the lock. HTH Dave

  7. #7tloft2012-05-01 08:39

    I don't believe anyone gets what Kevin is saying

  8. #8KevinK22012-05-08 08:34

    Wow..it's been an education! Thanks to the folks with the hints, Stabilizers down, loader fully rolled fwd to bite the dirt and front wheels of the ground, front slightly downhill, boom about halfway down, dipper & bucket fully in, RPMs to the governor, pull back and try your damndest to catch the boom over-center. It works! Friggin crazy.... but it works! I think I'll use the ext-a-hoe if I'm not on a finished surface (driveway, yard, etc...) I'm relatively certain that the worn piston seals make timing for the over-center reverse to engage the lock more of a challenge, all except the dipper and the loader piston seals (new) drop over time - the bucket, ext-a-hoe, stabilizers and boom all droop. I guess that's to be expected on an older machine. I wish they made viagra for hydraulics!

  9. #9dwloop2012-05-08 10:19

    They do... The seal kits are available on eBay, as well as the aftermarket pumps. :drinkup Glad you got it to lock, soon you'll be an old pro at it!! Dave

  10. #10KevinK22012-05-08 11:11

    Unfortunately, you're 100% corerct....this is the same routine that forced me to become a boat mechanic...which is taking up a lot of my time now too - gotta get her ready for the season - nothin' better than tuna or shark steaks on the grill, and if the tides cooperate, A quick dive on a favorite local wreck usually provides a few lobster to go with them!

  11. #11dwloop2012-05-08 11:15

    And a diver as well!!... I'll send you a PM to some of our dive pics!! We go as much as we can, not much diving in MO! Dave

  12. #12KevinK22012-05-08 11:27

    Yeah, Southern New England waters are peppered with wrecks and rock piles that hold lots of tasty critters. We spear a lot of bass and blackfish. Lobsters (bugs...) are always a target but they're nocternal and night diving in the good spots can get sketchy with our tides. I've had to hand-crawl over the rocks against the tide with the current trying to pull my reg out of my pie-hole...but I love bugs & butter...I had a lion's-mane jelly, about 14" in diameter, come right outta the dark and into my face once - that sucked a bit - my face looked like a road map from the 100's of stings. Just nuisance stuff, but it makes for a sore night. This year is looking good! Water is already warmed up to 52 degrees!

  13. #13Emerson2012-05-08 21:27

    I have the same problem with my 580K,, I always assumed it was because she's old and I never really worried about since the machine never leaves my yard. Good info to have though, probably make it abit easier on the machine when I'm driving around!

  14. #14Drc2012-05-08 22:17

    Yep. The up, then down for up technique, a case for improvemnt?