Got an old IHI 28UX 3 ton machine and it’s a bit jerky. I had gotten used to a nice 6 ton rental with smooth controls so this thing is killing me. It’s not as bad as those little china minis but still thinking about checking into this. The controls that bother me most are: 1. Blade. Coming down from being raised is slams me down. If I move extremely small amount it can lower slowly but its next to impossible to be that finely tuned just with my hand to lower it slowly. 2. Swing. Geez this thing takes off. 3. Main arm lift…when I’m lowering the machine from lifting it up off the grown that too comes crashing down. I saw a video on chinese minis slowing down the jerkiness so wondered if that could be applied to mine but the control valves or whatever they are installing would have to be rated for more. Thanks in advance for your knowledge! I’m getting new tracks and repacking some seals before taking it out to my property to work so I want to go over everything that needs work. I can probably live with this but if it’s simple enough I may made a mod.
The blade down and boom down could easily be slowed by a flow control valve, possibly even the swing. Do you think there is a problem with the control valve? Not sure of these units, are they pilot https://ad.doubleclick.net/searchad...S:CSM-2295:YF1CA5:20501201:APZ_1&gclsrc=3p.ds
Not pilot they are direct linkage to the valve body. I just don't much if anything about these systems. but i'm learning as I go. So if put a flow control valve inline will that not cause it to be slower throughout the entire cycle? Is there a way to have a "soft start" but pick up speed? I wouldn't want to lose digging power.
It will slow your volume of fluid through to the cylinder. In no way will it affect your power, simple fluid mechanics. I would expect you want it slower and more controlled throughout the whole range. It’s not like you will be bashing the boom, blade, nor swing, or so I wouldn’t expect.
Interesting. I'm wondering if they could be placed between a hose and metal line on the side of the boom. I assume only one needed per cylinder since fluid goes both ways. There's not a lot of room on the swing motor but i think it's just enough. I'll work it more and be thinking about how much I need this. Not sure if I'll start adapting to the sensitivity or what. It's almost like if I extended the control levers another two feet (although not possible) that I would have enough fine-tune control over the linkage to get that variation.
After some work done with the machine I wanted to follow up on this thread since I started it. First, I replaced the seals in the boom, dipper, and bucket cylinders. Of course this didn’t have any effect except that it stopped one of the tiny leaks and fixed some major pressure seal issues that I found including some that were just toast and others with the backing rings on the wrong sides of the seals. Yep. And those had been installed professionally. Then I added Lucas Hydraulic Oil Stabilizer at a 5% ratio then went up to about 7.5% to 8% ratio. It’s hard to know for sure because I lost some oil on the last cylinder repacking. I think the Lucas did a lot to calm down the jerkiness. I believe it’s just a thick and viscous oil that sort of slows down the flow. But not only did it calm down the jerkiness but it gave it more breakout and lifting power. The worn seals getting replacing probably also helped in this as well. I can now move the controls slow enough to have some finesse…it’s still a little challenging to obtain finesse but I am able to achieve it with slow movements.