SL 170-lll as above. SN 0192 (might be 0.192, but doubt it.) Odd request from possible buyer. "Everything moves too fast". I think maybe his operators are less than experienced. Seems about normal to me. But I had to ask. Is there a way to drop the flow or pressure and make things more sluggish? Idling down enough to notice a difference leads to stalling the engine, so that's not the answer. Open to ideas, or a hard shootdown. I really don't relish the idea of going through all the solenoids and trying to adjust things to run slower, even if that would be an option. The movement speed is a little subjective anyway, unless someone somewhere in a nice office decided it would be dangerous. I know on new CNC machine tools, the rapid travel speeds are a bit scary, and it was standard practice to back them off a little just because it seemed hard on the servomotors jerking things around and 2000 ipm. At least there are accel/decel parameters on those machines. Some may have a few pounds of fixtures and tooling onboard. Bad to thrash that around. Second, the swing motor (Kawasaki) had a broken dipstick tube in the gearbox, but it's threaded in, and since it broke at the threads I just cut more threads, and moved the rubber stopper at the top of the stick to correct for the new length. No issue there. But, there is a tube, a vent, about 1 1/8" diameter just sticking up in the air beside the swing motor. Never had any cap or anything that scratched the paint, inside or out and this simply cannot be right. I hoped for at least a check valve, but blowing in that tune ejected oil from the dipstick hole. Should there not be a breather cap on it? Thirdly, in the cab, right hand side near the floor is a control that I cannot determine the function of. It's stuck/frozen/non-functional. Any ideas? We do not have much of a dealer here for Daewoo, so parts and info are hard to come by. Looks like a common throttle control, but that function is taken care of electronically and works fine. Any input, even speculation, would be welcome.
1. You need to run factory cycle times on all your hydraulic circuits. That should point you in the right direction. They should be available from a Daewoo dealer or Daewoo tech support. I have found on quick hydraulic complaints the pilot pressure being too high in some cases. It’s worth a check. 2. That looks like the fill tube. It should have some type of cap on it for sure. 3. That looks like a mechanical override for your engine throttle control. It’s more of an emergency only failsafe in case you electronic throttle was to fail.
VeTech, we just got a new toy from a diesel laptop outfit. I'll see if it will connect to this machine. Our local dealer I think just took on Daewoo and doesn't seem to know much. They referred me to a third party woods machine service center, 75 miles away, who (I don't think I talked to the right guy there yet) didn't seem too familiar with them either. The must not be too popular around here. He at least agreed to try to come up with a service manual. I'll know more about that tomorrow. If I can get the manual, the cycle times should be there, otherwise I will call Daewoo (S. Korea) and escalate the call until I get someone who will tell me. 2)I think you're probably right on the throttle over-ride. It's one of those ordinary throttle cables seen everywhere, but I haven't removed enough sheet metal to follow it yet to see the other end. Kind of want to see a manual. I guess I can look at the throttle body, huh. 3)It just about has to be a fill tube. There is no other way to fill the gearbox other than the dipstick, and that's not happening. I'm sure it has a regular planetary gear system, but right now, surprise surprise, it's milky. It's enclosed, but who knows if it's been run with the hood up or left out in the rain So it gets changed. I'm just going to find a standard generic cap for it.
Daewoo equipment was more popular back maybe 15 years ago? Once the CEO scandal hit them they ended up in bankruptcy. I believe their only division left build train engines. Dealer support for the heavy equipment is scarce at best and you are likely to be dealing with service people that have no clue how most of it works and have limited access to past parts, maintenance, and service/technical info. The excavators I saw were actually pretty decent machines, it’s just the dealer network back then was a joke. I can’t really vouch for Daewoo now as I have no customers with them for quite a few years now.
Well, I hope I can get enough done to satisfy the potential buyer. Dipstick tube I fixed, I'm sure I can find a cap, or mod one to fit the vent tube, but I have no idea how to make the controls less responsive, or more sluggish. Propel speed is fine, it's just the tools that are quick to respond, and move quickly. Maybe I can convince him the operators will get used to it. Or if it is all common power supply, maybe I can bring the control voltage down a smidge and not have them jerking themselves out of the cab when they dig. It's got a dead thumb on it that isn't set right and really interferes with normal digging, but I don't know what his intended use is. Hes a rancher I believe, so digging stumps likely is on the menu so he will want the thumb. Too bad about their history. I didn't remember that. That's one way to kill a product. I will look into DFW and see if there is someone up there who might still support them. It seems like a basic, simple machine to operate so I see the appeal to a casual user. At least the AC works!
Minor issues taken care of, but I was told the sale is contingent on getting the bucket, dipper, etc under finer control. If I can't slow things down, no sale. So far, two dealers have been no help. I've been told the Doosan dealer in Shreveport is good, so Monday I will be calling them to see if there is a sneaky back door way to adjust things if there is no control function to handle this. It seems to me this should be part of the programming or a feature in the control. It kind of strikes me that there is a "power mode" that is engaged, but I can't see where to verify or change that. Parts of the LCD display are dark, so it's possible I just can't see it. One set of selector buttons that suggest a power level control have equine icons. One horse, 2 horses, then 3. These are not part of the LCD but are on a membrane switch panel below the LCD. Only one can be selected at a time, but I can't tell that they have any effect on tool response. Oh for a manual!
Hey guys new to this could any1 help me with a problem on a case 488p wheeled digger?
A pic if your monitor while it’s on with all your control buttons may help, may not. There is more than likely a service mode for the monitor where live values could be checked which would be helpful information....somewhat. Without knowing the hydraulic specifications for the system, then the values displayed would have to be assumed correct, which may not be. There is definitely different operating modes. There’s a possibility that could be the issue but I have never seen a mode that is “throw you out of the cab” fast on all functions. The functions are designed to match the torque curve of your engine to the hydraulic flow of your hydraulic system to accomplish....say “heavy lift” or a “dig”.....or “economy”.....and so forth. All of this is accomplished thtough the ECU working with a VCU and maybe other units. If I were to guess, I would say for some reason your pump is locked into a high flow, it’s just figuring out whether that is a problem caused electrically, mechanically, or hydraulically. A few pics of your hydraulic pump may be helpful as you may have a pump that has been used in other manufacturers equipment the may be more familiar......and may give you a specification base to possibly work with. A pic of the manufacturers tag on the pump would be awesome!
I also want to give you a brief example of why the monitor is important. I had a PC 400 Komatsu a few months ago that had a display that was broken and unreadable. The machine had weak hydraulic problems with the stick after running for awhile. The dealer tech for this area was called out by the customer and supposedly ran diagnostics which resulted in condemnation of the main pump. When I asked the operator what was done he replied that the tech ran the machine some.......and that was it. No computer Hook up and dam sure no monitoring live values since the display was unreadable. The first thing I did was get the cycle times from a member here. It required the monitor to be in A mode for the checks. No monitor.......no display......all I could do was push the A mode and hope it followed the commands. After running the cycle times I found that the crowd/stick functions were the only ones (in and out) that were off by a lot. It wasn’t a $25K pump issue at all. The customer was looking at selling this machine anyway due to rotec bearing wear And some other expensive issues. I recommended replacement of the monitor which after explaining why it was needed (Komatsu cost was around 3K if I remember right) they agreed. I found a new monitor for $1000, installed it, and immediately ran the functions on live values against the spec pressures I had. That just confirmed the problem was with 1 function which I already suspected by the cycle times done previously. The moral to the story is........ without a properly functioning monitor and the specs for your system, this whole thing will be a guessing game and can turn into one of those “parts changing” jobs that will be expensive and more than likely will not fix the issue unless you just get lucky with the right guess. Now, trying to guess at a cheap fix for the fast hydraulic speed issue, by twisting adjustments or tweaking things here and there trying to find a balance, will cause other issues elsewhere.......I can guarantee you that as fact. Then you will have a customer that has bought the machine and when those issues show up later.......guess who they are bitching to? Here is my suggestion, although some may disagree. Find a monitor replacement and specs for the machine. It will be the only way to properly find the exact issue. It may have diagnostic codes already in the system pointing you right at the problem......but you can’t see them. IF.....you can’t get both of those, the ONLY thing I would do is check the pilot pressure and adjust it ONLY. Lower pilot pressure can compensate the speed somewhat, but you will have to hunt for a well operating setting. If your pilot pressure is say 450 psi, drop it to 300 and see how it operates. If it’s to slow reacting......bump it up 25 psi each time until you find a decent medium. This will only effect the pilot controls and no other settings. By doing this you will be slowing the reaction times your main control spools have to react......but you also restrict the main spool travel with lower pressure to work with. Hopefully you can get this sold with minimal expense and your customer is happy with the purchase!
Good day Not the same model but if it is the display is similar I can post some information. Kind regards Uffex
VeTech, I'll get a pic up Monday. Just one this time. I don't know how I managed so many duplicates on the OP. Working around the house today. Borrowed a cute little Deere 17G to play with. But you're right on what you say. I'm working mostly blind. And as you said before, documentation is difficult to find. I did find a manual for a 300 LC, but that's a vastly different machine. Plus the 585 page book has a shortcoming...no or few illustrations came through on the scan even if it were similar. I've browsed it hoping to get a sense of how Daewoo does things, since that may help get my head wrapped around this. There are cycle times, but they wouldn't apply to the smaller 170, I'm sure. I'm not about to go tweaking the flow rates on each cylinder. In my view these are fairly complex, coordinated systems and I have no doubt there would be a ripple effect either now or in the future that would be undesirable at the least, costly and/or dangerous at worst. It does act like it is in high mode. I would bet big bucks that if the boom were extended and you stayed on the swing motor, in less than a minute the machine would be rocking off the ground from side to side. It might even try to tip over. It's a little disconcerting to spin around. Since you mentioned the pump, I'll say that the machine uses a tandem pump and it is painted a red iron primer color, likely just primed. From that I assume it is a replacement, but not being the correct red-orange, I'd have to guess it was a budget job or homespun. Not comfortable with either, and that does lead me to believe the adjustments are off or were never set when the pump was installed. It may well be a case of someone running in beast mode to try and continue using the machine after the pump began to fail and they needed the extra pressure/flow. I haven't looked for a tag, but will. Finding a complete display may be a problem, but I will find out about that when I talk with the dealer in S'port. I got sidetracked yesterday and didn't spend much time with this machine. If it's just the glass, maybe I could get a generic display and adapt it. But if there are permanent graphics etched in, that won't work. Maybe I can spot a used one. I hope I can get a manual still, and I'm looking. I'm hoping not to spend too much on bits and pieces, and just put some time into this, but I would like to see it gone. And since the potential buyer knows I'm working on it, it's important to me that he is happy with it. I have a reputation to protect. Hard to get back once it's ruined. There is a row of yellow and it just doesn't look right parked there . Well, the Kobelco doesn't match too well, looks like it's been in the sun too long. Uffex, thanks for that pic. It's similar but not exact. Items 12 and 13 are likely related to the problem if it turns out to be an operator selection issue. Looks different but I believe the same basic functions and options are there. This machine may be a low production model. The SN being 0192 tells me that unless that was stamped in January of whatever year it was built, they didn't build many at least that year. The membrane switches have an indicator light and they do seem to make/break but depending on how they light it wired to the switch it may be a separate set of contacts.
I googled “Daewoo monitors for excavators” and a whole Crapload of stuff with pics came up. If you remove the monitor from your machine there should be a tag on the back of it with a Daewoo part number........could be a different manufacturer if Daewoo OEM’d those from a contractor. That part number, whether it’s Daewoo’s or another, would be GOLDEN for you in your search.
I may have to retract my comment about the tandem pump being a replacement due to being simply primer color. https://www.terrapart.com/blog/wp-content/uploads/2015/06/DoosanDaewooHydraulicpumps.jpg I'll pull that monitor Monday and check the connections and get a pic or two of any tags.
After looking through a lot of Google images, I fail to find one that has the appearance this one does. Please see pics. As you can see, not all the segments are good, so I don't trust the readings. Also today I noticed that when the machine is idling, and the auto-idle feature is off, even at 1000 rpm and a gentle touch, trying to move the bucket, boom, etc. kills the engine. I can't believe it is really that weak, but in order to actually do any work or move things, the engine speed has to be up pretty high. Around 1800 and it will move everything without dying, but that may be part of why it seems to move "fast". With a soft touch on the sticks, I can move very slow and control everything just fine. There is also a noticeable "step" feeling when moving the sticks. A slight move is fine, but for instance, spinning around, as I push the sick further, there is a point where it feels that an additional solenoid opens, or the pressure (and speed) jumps up significantly. Maybe that's a clue. If I were to disable that, it would solve the problem. It seems there is a mode issue to me.