Greetings, I have a Dresser/Komatsu 6220 LC excavator serial number 2060004U001034. I am told it is the same as a Komatsu 220-5. I bought a repair manual online and it is not the right one. This machine doesn’t have the digital code display behind the seat for diagnostics. The problem I am having is that the arm cylinder has no power in either direction and drifts very bad. I just bought the machine and cleaned the screen in the hydraulic tank and replaced the hydraulic filter. The filter was loaded packing material. I also took the arm cylinder to a reputable hydraulic shop and had it repacked. They said it needed packing bad but the cylinder was in good shape otherwise. After putting it back on I still have the same symptoms. No power, bad drifting. All other functions work well for a 25 -30 year old machine except the left travel is a little slower and weaker than the right side. All the settings on the monitor change when the different buttons are pushed. Fo,Ho,etc. I have read that there are some inline screens in the hydraulic system but I don’t know where they are as I can’t find the right manual. I even emailed Komatsu headquarters and my local dealer with no response. Any help would be greatly appreciated. Thanks
I have not worked on any of the Dresser rigs but have plenty of experience on the Komatsu Dash 5 line. It sounds like you did the right things to start with. There are two valve spools for the arm function and one might be stuck partially open. You can follow the hoses and piping back from the cylinder to locate them in the valve blocks. The other things to check for the power and drift problem will be the circuit relief cartridges. There may are packing material stuck in the poppets. You can remove the cartridges and dismantle them to check. They are pretty simple to take apart. Inside you will find a spring and cone. If the cone has a ring worn into the surface you will have to replace the cartridge. New cartridges are set at the correct pressure already so they can just be screwed into the valve block. If all this checks out good, there is the possibility of the valve blocks being damaged.
I did take the relief cartridges out . There was nothing stuck in them. I cleaned them and put them back in.How can I check if the spool valve is stuck ,can I take them out where the Allen wrench screws are without anything falling out and me losing it? Thanks
Does anybody know where I can get a manual for this machine using the address or serial number in my original post? Service/repair manual. Thanks
By the way, in the title,I missed typed/ had a brain fart it should say Dresser if this can be fixed I would appreciate it. Thank you
Free of charge, friend. Good luck. https://www.mediafire.com/file/gvqag0n1d8wpb9s/PC200_220LC-5_SEBM02050508_SHOP_MANUAL.pdf/file
Thanks alot, hopefully I can figure something out. Do you know if I can take the spool for the arm out of the valve body while it is on the machine? It looks like all I have to do is disconnect the pilot line then take the Allen bolts out. I don’t know if I do this is there anything I can inspect,clean or fix?
You are correct on checking the spool for free movement. If one of them are stuck, you will have to carefully tap it from each end to get it to free up. Good Luck
Can I take them apart on the machine?
Yes, all you have to do is pull the end caps. There will be at least one spring or maybe two on each end of the spool. You will lose some oil so be prepared with some kind of pan under the machine if contamination is critical. You only need to pull one side of each spool and if it moves easy, the spool is OK. If it is stuck and you have to free it, you are probably better off to pump or drain some oil out of the reservoir to below the level of the spool.
Thanks alot I will do this this weekend, hopefully I will be back in touch with good news! I am an equipment operator for a large company and run new iron every day. This is so frustrating running this machine knowing it’s potential, even if it is 25-30 years old.
Hi Lachau,the manual you sent me is the same one I purchased online and is not for my machine. I suspect my machine is for serial numbers earlier than the ones listed as my machine does not have the digital diagnostic readouts behind the seat. Would you have access to the earlier manual? Thanks
You should take a few photos of the device, this will be clearer and easier to discuss. It's same as below???
No, These are some pictures of the pump and the monitor it looks like a Dash five but doesn’t have computer monitoring
If your machine has a dial for the throttle control, it has to have a computer. On that model of machine there are two computers, one for pump and hydraulic system control and one for throttle control. If you remove the cover from the side of the right side console, I'm sure you will find a computer a little behind the seat. The readouts will be on the face of each computer and will be reversed. They are meant to be seen through a mirror.
I thought the readout “screens” were on the outside of the cover, not inside,I will check this out this weekend!
There usually are tip out mirrors on that panel that are behind the operator seat and the heater is stuck in next to them. A lot of gray market Komatsu excavator came in and didn't have the mirrors or only had one and a peekaboo hole for check the diodes on the throttle controller. Komatsu did make a special model that didn't have computers, only a monitor panel. I was told by the Komatsu rep at the time that it was for working in rice paddies. I'm pretty sure the Dresser machines were all standard though. A photo with the console panel off would identify exactly what you have.
I will get pictures this weekend, you guys are great!
hey jersy john this is albert clsark the builder from maine how are you doing i got a yanma v1070 lost my hydraulics in my joy sticks it was runing fine just like you unplug it the blade and thumb works fine and it travels and steers fine starts and runs well let me know if you have any ideas what it may be
The tipout mirrors were there just like you said! I didn’t realize that they open like they do. I started the machine and the bottom one has a solid green dot on it. The upper one has 2 codes flashing, one is 5.2 the other is 8.1 The confusing part is that I took a picture of the codes with my phone onthe mirror and it is.1.8 and .5.2
The 52 is actually S2. The 18 code means disconnection in TVC solenoid. Check under the glove box and you will find two toggle switches. As I recall they should both be pointed toward the rear of the cab. One of the switches is for the pump control while the other keeps the swing brake off all the time. If they are set correctly, look on the pump and you will see a coil. Check the wiring from that coil back into the main harness. You are likely to find the harness connector unplugged.
Before I forget, there is the dot light in between the digits. It should be flashing. That is the signal from the speed sensor. The faster the engine is running, the faster that dot will flash. The speed sensor can be shorted through I think and you won't get a code but the dot will either be out or on all the time.
From page number 312 to 315 in manual which I sent you already .
I know where those switches are, I don’t get any reaction to the pump control switch in either position. This Tvc solenoid is on the pump on the back of the engine correct?
If both switches were the wrong way you would get a 14 and an 18 code. Yes the coil is bolted into one side of a control valve on the pump.
Is this the tvc solenoid?
Yes
OK, its plugged in. I followed the wires back to the hydraulic level sensor haven’t gone any further. what kind of voltage should I be getting from the plug so I can see if I’m getting anything from it? I also forgot to check to see if the red dots are blinking in the display for the engine speed sensor. Will do that today. Thanks again. Also as I said before nothing changes withe tvc prolix switch in either position, I see there is a resistor in the wiring diagram, I wonder if it is bad?
I've never checked the TVC for voltage, only checked the coil with an ohm meter. If there is no connection to the computer, the computer puts out the code. The resister is for bypassing the voltage past the computer. It only gives enough current to the TVC solenoid to allow the pump about 3/4 of its maximum output. What is odd though is that when you disconnect the TVC, the pump should go to maximum output all the time. It should overload the engine. Try disconnecting it see what happens. Your machine is old and it is pretty common on these pumps with that much age for the little spools in the valves on the pump to get stuck and not do any regulation.
I’m getting 26 V coming from the plug that plugs into the TV see solenoid no change with it unplugged and I’m getting about 15 ohms on the solenoid
I Also forgot to say the red dot is blinking and does change with engine speed so I guess the speed sensor is OK
TVC Valve = T orque V ariable C ontrol Valve. Normally TVC valve 's controlled by PUMP controller, if the pump controller is failure, TVC valve's connected to battery directly through resistor.
Do you have any thoughts on my voltage and ohm testing results?
Take the solenoid off the pump and leave it plugged in. You will see a plunger on the end of the solenoid. Have someone turn the key on and the plunger should move when you shift working modes on the monitor panel. If it doesn't then it is stuck and you will need a new solenoid. If it does move, then the small spool on the opposite end of the valve is likely stuck. There as an adjusting screw assembly held on with two bolts. Don't touch the adjusting screw, just pull the assembly off and you will see the spool underneath. A couple of times I've had to use vise grips to pull the spool out, clean it up, blow out the hole with some solvent or ether and reinstall all to get things to work right again. Good Luck
Ok, I will do that tomorrow. What are these electrical devices and what do they do? They are on top of the spool valves. By the way I took offthe end of the arm spool valve and it wasn’t stuck. It was clean and moved in and out smoothly and relatively easy. I put it back together and the slow, weak movement on the arm only is still there. I have been seeing alot about the arm half flow solenoid/ valve. Where is this located? Thanks
I took the solenoid off this weekend and with the key off the plunger is retracted. When I turned the key on it comes out, changing work modes doesn’t change anything in the amount it moves. I also created another problem as I took out the small spool and cleaned it up. The o-rings and plastic spacers were brittle and falling apart. I tried putting it back together and can’t get it to seat. I have the spring and plunger lined up but it won’t go the last 1/4”. I got the bolts started and tried tapping and tighten it. Does anyone know where I can get a seal kit,or a reasonable price on a rebuilt Tvc valve unit? Thanks
All that stuff from Komatsu is ordered as individual parts. No one makes kits for that kind of stuff. On the small spool, did you maybe turn it around and try to put it back in. Hopefully, it only goes in one way correctly.
I tried it both ways it won’t go in
Are you talking about the sleeve on the opposite side of the solenoid?
Yes
I seem to recall you had to put the sleeve in all the way first and then install the little spool after wards. It might also be that the sleeve has to be turned just right in order to go all the way in but I can't see that on the drawing in my book.
I tried many times, turning it different ways. I plan on draining the hydraulic oil and removing the whole valve block from the pump and taking it apart and cleaning it up and putting new seals- o rings. That’s why I asked if there was a kit.
I wish there was but no luck on any hydraulic kits anymore on Komatsu machines. Last I worked on even a cylinder, all the seals and wear parts had to be ordered separately. Good Luck
I don’t know if the moderators look at every post but in my original question I put down that it was a Drott, it is a Komatsu /Dresser ,maybe I would get someone else to chime in?
I saw it but didn’t really care. It was easy to see what you were talking about in your posts.
for your reference.
Thanks
Can you send me a picture of the rear nco valve in detail?
Rear CO-NC valve ( C ut O ff - N egative C ontrol Valve).
Thank you very much!
So I had to buy new negative control valve parts #7,5,32 and related seals. I installed them and now the machine has constant pressure making the arm go out. Pulling the control lever in does nothing. I have zero response from the control lever.All other functions work. Where do I start?
By the way those part numbers were for the photo above.
I would probably tee into the arm in pilot fittings at the valves.
Tee in and do what?
Operate the function and see if there is pilot oil pressure pushing the spool.
The spool was stuck for the arm. I freed it up and now the arm works again but slow and still drifts. I guess there must be something wrong inside the valve body on this function.Do you know what the blue part with the black knob is in this picture and what it does?
It's a solenoid coil. I don't know what that particular one does.