I have 5 position valve The center has a float to let the boom swing during transport so I can see adding restriction might not work and didn't even I added a valve. The boom swing rotated too fast no matter how slow I have the engine running. It really messed with operator. How would we slow this down?
My father’s iron mule just used 1/4” hose for the swing hoses. I never thought it was too fast. Maybe someone swapped in a bigger gpm pump on your machine at one time. A lot of continuous grapple rotators use hydraulic fittings with a very small orifice drilled in them to slow them down. Perhaps weld a fitting closed and drill it out till it meets your needs.
I tried to regulate it with a valve but didn't work. The grapple rotator works fine. It's the boom is the problem. It does have small hoses on that cyl. It really flys, way beyond distracting and dangerous to work around.
Just wondering does the main boom also have a detent on it too? My dad’s did. I rebuilt the valves 7 years ago with new bearing balls in the detents along with new seals. No longer need the rubber snubber to keep them in detent any more.
Kind of half ass stuff you do not want to share but. Farm tractors got bigger and were blowing the seals out out the hydraulic motors on Balzer vacume tanks. Also over speeding the pumps - compressors. Trucks lined up in the field bumper to bumper. Under the gun. Brazed the inlet fitting solid and drilled a hole in it. 1st 2nd or 3rd try I don't remember but it was small. Only an 1/8 or 3/16. Life was happy after that.
You can get hyd. flow restrictors to put on the lines going to the swing. Lots of guys with angle snow blades on skid steers use them.
Ok, this sounds like progress. I do not have a drawing but this sounds about right. When I tried restriction it even st various settings it simply stopped or didn't make a difference and then realized the same thing about the swing. The valve I used was not a real proper valve, I simply used it for the test but when I turn it to slow it simply squeals when I regulate it enuf to slow. I can imagine I am not the first to have this problem and would have thought someone would have fixed this had it been easy.
Pressure compensated flow control ,, sounds like something I could find at surplus center?
I had thought restrictor but don't think that will work. My hyd needs are simple and we always had JD which confused me early on and I haven't been right since. I fix cyls and leaks and am quite the plumma but I don't know anything about it and just plain don't work with it enuf, never had the background and it's almost a stretch to figure out a log splitter. Seems there was some kind of valve on one still wasn't sure about.
Make sure there’s no air trapped in the cylinder. Air in the system will make it move very fast even with a restriction in the line.
Case 580 K Backhoe was notorious for excessively fast swing. I knocked a hole in a wall with it. Open center hydraulics have feathering grooves to allow some flow downstream, but it wasn't enough. Two or more functions at once it swung slow. When I stopped other functions, it took off like a bullet. Case first put flow restrictors, then larger swing cylinders to slow function, then a swing sequence valve. None really was a perfect solution.
Can’t limit the spool travel,fixed my lowboy ramps that way
I take it the valve has some kind of pilot? The pressure comp valve? No, I dont think I can limit the spool in this case. Even running 2 at once doesnt slow it much. Everything on it looks factory, dont think its been messed with but find it hard to believe it came that way?
I used to have a flap/guard on a cutterhead that would slam way to fast because the 2" cylinder was small for the given flow rate on the accessory line. A simple flow restrictor that I picked up at the local farm store hydraulic section for about $5-$10 and mounted at one of the line inputs on the cylinder solved the problem. If things move too slow, you can always drill out a bigger hole in a restrictor but do it a few thousands at a time. It does not take much to really speed things up. I have used these on a couple different projects as well as the needle valve style that will allow you to tune the speed. Some of the needle valve style are one way restrictive while others are two way restrictive. fixed flow restrictor variable flow one way
I am going to consider that again but dont think its going to work Te man is on to it in post 7. I was hoping I could simply restrict this, tried it with a valve.
If you put the restrictors as close to the valve as possible, they should have much better results.
I can try that. I was hoping for the magic forum answer.
I know nothing about your machine, its valves or what fittings it uses, but you can slow the swing function down using two adjustable flow control valves fitted inline with the lines that go to the swing actuator, whether it's cylinders or a motor. But assuming your main control valve is fitted internally with anti-cavitation valves for each valve section, which many are, you would need to use adjustable flow control valves that allow free flow in one direction and restricted flow in the opposite direction. The valves should be installed so the free flow is the supply to the swing actuator and the restriction is on the return side of the actuator. Keep in mind though, depending how much you're using the swing function during operation, restrictions in a hydraulic circuit can cause heat. If the swing function is being used, like all day long, it can heat up the hydraulic oil excessively.
Thank you so much as I had been thinking the same thing. Grainger - Parker F400B. If he does not understand the top line with an arrow is adjustable flow rate to the cylinder. The bottom is a full open return flow check valve. He would need 4 of these, one on each line of the two cylinders. Swing on my old 680 is very touchy but not that bad. There is something else wrong with that machine but it could be made to work this way. That is not the correct way but a will work way. Where is Tinkerer? He would know the correct way!
Agree, this ain't the correct way, as a proper system shouldn't need this. But since that's where we are and have no clue why we're here, it is a workable solution.
Maybe a priority flow divider would let excess flow go back to tank without causing excess heat? A good hydraulic shop would know the best way how to do it.
Exactly. But it is more expensive for the components and have to run return lines to tank. It's more proper, but as long as operation isn't continuous to build up heat, adjustable flow valves will work fine.
i have a question what kind of pump do you have on this machine ??
For sure, I have a lot of questions, such as you stated, what pump do you have? Is the system open center or closed center? Why does only the swing work fast where other functions are normal, is there a freaky priority valve in here somewhere? Are there anti-cavitation valves on the valve sections? Just to name a few.
I'd almost guarantee it's an open center gear pump being it's likely an early 70's machine.
I wouldn't mind the correct way. I might look and see if I can find factory setup? It had to be better when it was new.
It's open center. I don't see any priority. I don't see anything special on the valve body and the only different section is this one and it has detent to put it in neutral
Got a common pump on the front of the engine.
In that case I would probably try and experiment with a hydraulic flow restrictor. I can’t see you using it enough to overheat the hydraulics, Another option would be to plumb in a small pressure relief block along with the restrictor but you would have to also plumb in a drain. Do not think this would work very well. What I have done is, on the JIC fittings, you can take a small flat washer that fits in the bottom of the line, not the flare and cup it with a ball peen hammer and install it as a flow restrictor and experiment with hole sizes. Cheap and easy way to try it out.
Yes, I have done the home made "orifice washer" inside a JIC fitting before to regulate the speed of an actuator. It's an effective and cheap fix to be sure. But in this case, without knowing the valves on the machine fully, I'm really concerned about anti-cavitation, which most control valves incorporate. Just don't know if this one does. But if it does, anti-cavitation is an important feature. Adjustable flow control valves with reverse free flow fitted as I described will not disrupt the anti-cavitation feature of the main control valve. I really think this is the best, least expensive, and easy solution in this application.
Agree
This is simple low power open center system. The valves look common, like on a log splitter. What is cavitation in this type of system?
I have same system with a box rotator on a forklift and added a needle or orifice to slow it down but,,, valve does not need to set in neutral detent during transport
Valves that typically supply oil to actuators, cylinders, motors, that work things like a boom on a backhoe, if there is a force, like a boulder rolling over against the side of the bucket, and does it with enough force to pop open the port relief valves in the control valve, that force will swing the boom forcing oil through the port relief valves. But on the other side a vacuum has been created, that will cause cavitation which will damage hydraulic components. For that reason control valves in applications like this typically have anti-cavitation valves integrated in the valve ports to prevent this from happening. Don't know if your machine has that, but it's possible.
I'd think it's a very basic open center hydraulic system, nothing special. All it needs is to slow the swing speed down. Flow restrictors or a priority flow control should solve the issue.
If it worked I would have left it at that and felt like a genius and if I knew what I was doing would add a priority valve. It is simple but has a special requirement. Needs to be in neutral during travel.
Can I ask a question related to a different machine? We've plumbed the backhoe for a thumb. Put a selector valve in a stabilizer circuit. Power on, it diverts function to the thumb. We have added a port relief valve in the push line. This prevents damage when the bucket pushes against the thumb, but won't prevent vacuum in the retract end of the cylinder. It's unlikely this will happen more than a few times a year. Will this cause damage?
Not sure, I have a diverter hooked up to my tilt cylinders and front hookups for my plow with its own pressure relief valve and I have had no problems with it for 3+ years. As far as I know it’s like a closed loop because it doesn’t have a separate return.
Doesn't the control valve have spring center to neutral that holds it in place?
I believe Sberry meant to say it needs to be in the detented float position during travel. The loader boom is part of the front frame on these machines and it rests on the rear half during travel. Thus when the machine articulates the boom can swing freely with it. These machines do not turn excessively fast so I’m sure an orifice on the boom swing function will not make a huge difference. I think some of the trouble the OP is experiencing is the fact that the loader uses a single cylinder operating a rack and pinion to slew the boom. I’m sure due to the differences in volume on base and rod ends of the cylinder one direction is much faster than the other. On the machine I’m using 4” bore 2” rod. Mine is much faster to the left than the right. It takes some getting used to.
It has a detent when it's pushed all the way that must hold it open/
I hadn't thought to which side is faster. Yes. That is what I was looking for ,, float.
So boom left is faster but boom right is stronger? Has it been confirmed that this is how the machine typically behaves, even when new? Have you asked the seller? Seems likely there is something either worn, broken or misassembled on this old girl. Take it apart and see if there is anything obvious...
The seller wouldn't likely know. I think my helper signed me up on forestry forum but haven't had the chance to get there yet.
I wonder if there's a flow restrictor that slows the faster direction? My backhoe uses a rotary cylinder for swing but the fittings on the rotary cylinder are much smaller despite the ports on the valve being the same. I think it might reduce the 1/2" down to 1/4" or it could be 3/8". Earlier backhoe models used a rack and pinion swing. Curious if all the functions are excessively fast? Wondering if perhaps someone put a higher GPM pump on the front. The grapple was added so maybe so was a bigger pump??
The rest of the equipment is stock, same pump etc. the swing is a rack with big cyl and small hoses that pretty much look like they been there forever. Almost looks like the valve body hasn't been apart. Grapple changed but it came with one, doesn't look like those spools were touched
There is ample evidence that the body has been molested. Every color of shiny and dull nuts, links and pins. The collars are paintless and held on by partially stripped screw heads.
I just cleaned and serviced all that stuff, resized it so its tight. I drilled some up, had some 9/32 I put in some worn holes. Some up to 5/16. Ground the worn pin out of the link plate, drilled both plates and the collar up, welded bigger pin to 1 plate. Welded holes in the levers and re drill.
I did the boom lever first and really fit it exact and got a bit lazier as I went and could go back if it mattered much and hypertighten a lever yet but its really irrelevent at this point. Had helper with some shields and stepos again in some leak work and going to see if the leaks in a spot slow as the fluid levels drop some. I think it sits at an angle and messes with the dipstick and we topped the levels off.
I see I have a leak from the backside of the steering valve, its minor and will think about it if we paint. I need to make a couple minor covers, wouldnt mind getting it housebroken at some point and I try to paint equipment I use regular. I have a loader only seldom used not painted but its not worth it for sure and wouldnt change its value a whole lot.
I painted a yellow job a while back but didnt take a pic. When they are rusty it takes a lot of sanding to make them nice, we can sandblast but its really not great just due to grit. I was considering a rust laser but ditnt know anyoe has one. Was a guy on WW had one for a while and said price had went down but its something that interests me a bit.
If it uses a single cylinder for this swing operation, and if the control valve outputs equal gpm of oil out of A and B ports to the cylinder, then retracting the cylinder, whichever direction that is, left/right, will work faster than extending the cylinder because of difference in displacement between rod side of cylinder and piston side of cylinder. Again, if you install adjustable flow control valves on the two lines with free flow reverse you can dial in the speed of the cylinder movement extending and retracting independently thereby matching speed in both directions.
Ok, I got to read this again ha
It's simple physics and hydrodynamics bro.