Boom falling fast question

[David storm]

i have a case 580c extendahoe and the all the controls work fine except when I boom down it drops like a rock. now if i reach out and down at the same time ever so slightly i can move pretty smooth. I'm not sure if its a cylinder problem or a valve issue. any info would be great before i start tearing it apart.

Thanks

 

[Tenwheeler]

I never ran into exactly that on my 680 but I have learned this. If it has a cylinder bypassing on a duel cylinder application I can isolate this way. Start it cold and hold the lever all the way in one direction for 2,3 or maybe 5 minutes ( at idle ). The bad cylinder will be warmer than the other from fluid passing through it. Maybe hold the boom down and the hoe levers at the same time. If the boom cylinder is hotter than the hoe cylinder I would look into the cylinder. I would use any other cylinder except the reach out. My thoughts are if the two have some type of interrelated valve problem it could mess up the cylinder heat test. Let us know what you find.

 

[Ronsii]

doesn't sound like a cylinder problem if you can control it like you say.... One thing you don't mention in your post is did this just happen suddenly or getting worse over time.... or always done it?

 

[Andy01]

My 580C is the same way. Very touchy booming down unless operating another valve at the same time. Only backhoe I have every used and it is fairly new to me but I am used to it now. Every function seems to work smoother and or slower if operating 2 valves at the same time. If you find a solution let me know.

 

[fast_st]

Newer equipment have valves that prevent cavitation, lower the boom and lowering the loader arms can be a free-fall operation on the old Case. Operating two valves at once puts back pressure on the head of the boom cyl to slow it down a tad. There is so much static load on the boom cyl that it really wants to not be up in the air. Like the loader arms, if you let it drop, it takes a little while for fluid to fill the other side back up again, if you drop and then push down, there's a pause before the action starts.

 

[Tinkerer]

Do you have a service manual for your 580 ? There are ways to determine what it is malfunctioning in the service manual.

 

[fast_st]

Might be that your control is a little sticky mine barely needs a nudge before it'll drop, sometimes you can sneak the cross bar up to knock all the rust of it.

 

[David storm]

Thanks for all the replies, ive only had the 580c for a couple months. I bought it to clear out palmetows on a lot I have and ive used it quite a bit and at first it probably look pretty funny watching me working with it but now ive figured it out pretty good. this one is and old 1980 but still in good shape. Im in the process of restoring it some,replaceing bushings,pins,did a complete brake job on it,planning on paint.
anyway as far as the dropping boom it does pause when dropping all the way down and starting to dig. So it may just be something I have to live with. I was hopeing for a fix but it does still dig pretty well. I will check the manual,didn't think of that

 

[xgiovannix12]

my 580c does the same its the way the cylinders on the mainboom were set.

Lets see some pictures of yours Mine is a 1980 as well

 

[Tinkerer]

It could be something as simple as the boom cylinder gland separating from the rod. Booms dropping unintentionally is not normal in any backhoe or end-loader that I know of. There are backhoes with a quick drop function designed into them. Similar problems on different machines can have completely different malfunctions.

 

[fast_st]

It could be something as simple as the boom cylinder gland separating from the rod. Booms dropping unintentionally is not normal in any backhoe or end-loader that I know of. There are backhoes with a quick drop function designed into them. Similar problems on different machines can have completely different malfunctions.

Well, its not unintentional once the operator selects boom down, but it should be marked boom down now! Its also good for hammering the bushings while pounding a backfilled trench, so I've heard! It does have complete control but if you give her a big fistful of push on the boom lever, she's a goin!

 

[Billrog]

The boom cylinder has a restrictor in the out let or should have it may have been left out at some time after a repair.

 

[poempijus12]

i have a case 580c extendahoe and the all the controls work fine except when I boom down it drops like a rock. now if i reach out and down at the same time ever so slightly i can move pretty smooth. I'm not sure if its a cylinder problem or a valve issue. any info would be great before i start tearing it apart.

Thanks

write us on info@poempi.lt we will send you drawings of the part you need

 

[Tinkerer]

Well, its not unintentional once the operator selects boom down, but it should be marked boom down now !

I was referring to the unintentional high speed drop in that statement. I see what I typed it could be misinterpreted.
Fast boom drop is covered in the service manual.

 

[David storm]

very good,i will check it out once I figure were the b port is at,Thank you

 

[Tinkerer]

very good,i will check it out once I figure were the b port is at,Thank you

You must not have the service manual. Download and save from here ------> http://files.minnpar.com/partbooks/...MANUAL/Case 580CK Series C Service Manual.pdf

 

[David storm]

After using my backhoe for quite a few hrs now the boom seems to be working pretty much like it should. It sat up for quite awile and I'm guessing some vaulve was sticking and freed up now,im very happy for that .
But now ive noticed lately that the loader bucket will not stay up. lift it and watch it slowly lower on its own. lift the machine and it will not hold it up. Is there a fix for this?

 

[fast_st]

Well, if fluid isn't leaking out on the ground, likely its the valve leaking and letting things settle, does the bucket slowly dump as well? could be chewed up valve o-rings

 

[check]

The boom cylinder has a restrictor in the out let or should have it may have been left out at some time after a repair.

If you have a restriction on the outlet, I think it would cause the boom to raise slowly too, which is undesirable. It seems they would use an orifice-check to prevent that. An orifice check restricts flow in one direction and allows it to free flow in the other. Maybe there is such a valve somewhere and the check valve portion is worn or stuck open. It would be positioned in a line between the control valve and the cylinder.

 

[Archie Dunbar]

very good,i will check it out once I figure were the b port is at,Thank you

David did you solve your boom falling problem yet? I have a 580b. I think it digs pretty strongly, has no problem lifting full buckets with the boom. But it definitely has a fast drop on the boom if I forget to be easy with it. I will check the flow restrictor. The B port is the lower one. I am waiting for a 1 1/4 inch crowfoot wrench to come in the post so I can get to it without taking all of the adjacent hoses loose first.