I'm having a hard time locking the boom on my machine. I know that when it goes past center, the valve is supposed to be moved to the down position which results in additional movement to the rear. I can almost get it back far enough, but so far have been unable to make it lock. Also, this drawing shows some parts that I don't have on my machine. Were these items a option or have they been removed? I don't have a operators manual so will someone please talk me through this?
You need to have it close to half throttle to get it moving fast enough to keep going when you move the lever to the down position. It will seem pretty violent the first time you get it, but after you practice, you will be able to lock it without even hitting the stop. Exact procedure is as follows: start with boom about halfway to the ground. Increase throttle to about 1500 rpm, pull lever to bring boom up, right as it reaches the top, quickly move lever to the down position. This will keep boom moving towards the cab and the ring should drop over the top pivot pin. If the strap the holds the ring is missing, it will be impossible to get it latched. I can latch it starting almost at the top. You just have to use the release lever to hold the ring up a little so it clears the pin when you bring boom forward.
I hate to sound like a complete idiot, but what do you mean when you mentioned "hitting the stop?"
There should be a rubber bump stop under the lock ring on the front of the boom. When the boom is in transport, it cushions the boom against the swing tower. I always keep hydraulic pressure holding the boom tight against the bump stop to prevent the boom from banging around on the lock ring. Read my previous post again. I added a bit.
That makes sense. Yes, I have that rubber block. I thought if it was some kind of control I was supposed to move, either I couldn't find it or it is missing. Got any idea what those boom lock parts are in the drawing? My machine has none of those.
Maybe circuit for a quick coupler? Honestly have no idea. I ran 580C, 680E and 780C machines. BTW, until you get proficient at locking the boom, it's easier to do with the stabilizers down. Less machine bounce to contend with.
I should have put this in the first post but the title of that drawing is " Boom lock, hydraulic and electrical circuit." I don't have a clue what it is but if it's not needed to get the boom to lock, I'm gonna assume it's a option of some kind and forget about it. There are a lot of things I'm not proficient with on a backhoe yet. Thanks for the help!
I have had several Case hoes, and have never seen the parts on the diagram. My educated guess is an optional electric control to unlock the boom instead of stepping on the pedal. There have been several threads over the years of people new to the Case machines and having trouble getting the boom locked. Once you get the motion, it is easy. You are relying on the momentum of the boom to get over the center point, then a quick push of the boom lever the other way to push it forward and into the lock position. I agree with Shimmy, it is easier to learn with the stabilizers down, but once mastered, you can do it even while driving. One key to not slamming it is to learn how much to push on the boom down once it gets past center. it only takes a little bit, the timing of it is more important than the amount of force. Don't feel bad to not get it, we all had to learn, and until someone showed us the right way, I am pretty sure every Case operator looked bad at least once while learning how.
iv ran one of the new ones(580) it had a quick disconnect in the cab ,boom lock was like what your talking about. always wondered about cases style of boom lock why?
Grc61, The over center boom lock on the Case stores the backhoe so some of the weight is transferred to the front of machine instead of just hanging off the rear wheels. This generally makes the backhoe more agile and road better with less porpoise’ing.
Played with it today and in just a few minutes, got it down. You have to get enough momentum built with the boom to get it off center enough for the cylinder to be able to push it the rest of the way. When I bought this machine, the boom lock was removed and when I saw that drawing, I figured some other items were removed as well. THANKS GUYS!
i agree
yeah I understand the purpose but I don't know why push boom away from machine to bring it up
Geometry of the boom and cylinders.
Since the boom goes over center, extending the cylinders actually pushes the boom forward for just a second. My 580D has the older style lock (looks like a ring on a pin) When I unfold the boom I push the boom control down and it relaxes on the pin making the lock lever easy to unlock.
i got that crappy video i just made to give you a quick view sorry for the bad quality and the lever slip off my hand due to oily glove the hand trothle is frozen so a brick on fuel do the job https://www.youtube.com/watch?v=i7lkp26uYj0&feature=youtu.be