So I bought the hyundai I was looking at. Sat for 8 years so fuel was **** but still ran strong. Good price, cummins 6cta 8.3 runs really well no blow-by, smokes a little so need to clean injectors and pop test them. Has a kawasaki K3V tandem pump on it, hydro tends to run at 120-140F when working hard. F#$%ing mice ate some wiring and had a small electrical fire...oops. No gauges work so I replaced all the gauges with new cluster, added oil pressure , EGT, tach, rerwired all the things to get running after the flame out. Still need to do the safety lock out, and travel speed switch, horns and lights. Changed all the filters, oil in motor, cleaned hyd strainer and found after extensive research the return hyd filter. At least I know the filter #'s now. The main issue is the hydro seems glitchy, when moving the dipper either in or out a full stroke will stall motor, also travel tends to really bog down motor. I got a manual off flea bay that was ****, worst manual I have ever seen, no Hydro schematic, and it was a couple years older than my machine since it shows a computer on the machine. So.... Is there another Korean machine that would have approximately the same hydro setup so I could look at that schematic to diagnose the hydro? I heard these Korean machines were mostly the same at that time period. I dont beleive the pump is bad I think it would be contamination in the main control valve, or maybe the regulators on the pump. Pressure / flow wise. Alot of the wiring was either disconnected or rotted off the MCV, I believe that they are sensors wired in series for hydro dummy light? They are definitely not solenoids. This machine is almost completely mechanical other than the safety lockout sol, and the travel speed sol. So again any info or suggestions would be greatly appreciated, this excavator is going to be primarily used for farm use so just looking to get this reliable and strong.
Hi Rik, You can download shop manual here for free. Good luck http://ce.hhi.co.kr/eng/parts/sm/R290LC-3/c_exca1.htm
Good day Silk If we can assume that your 280Lc is the same as the 290-3 then we can see we have a PWM valve connected to the pump regulation, the function is to prevent engine overload, as you mention you have had some wiring issues may I suggest you check this out. The easy way is to connect a guage to the pWM outlet port and observe the pressure as the engine loads increase, the output from the PWM should increase with load. Begin with this and move on to resolve other issues, hope this helps. Kind regards Uffex
Thanx guys, yeah the manual def is clearer than the rat nest that I bought, the 290lc-3 is similar but mine has no electronics, no wires coming off the regulators or pump for that matte, so no pwm. Its strictly a mechanical setup with the only electric solenoids on the travel and safety lockout. But def helped with the manual much clearer and more info is always better
Oh and anyone know what all the sensors, what I gather anyways, are on the MCV, do you think they are pressure? or temp? Havent gotten around to checking them with a meter while running yet.
Good day Silk If you have a couple of pressure switch's at the MCV the chances are these provide a signal primarily for auto Idle, may I suggest that you take some good picts. of the MCV and pumps including the tags that way we may have a much better idea what you are dealing with. Kind regards Uffex
Good day Slik If you have the correct hydraulic schematic however poor for your actual model that would be usefull to supprt you. Kind regards Uffex
IMG_2287 by richard heydecker , on Flickr HERE IS THE PUMP TAG IMG_2357 by richard heydecker , on Flickr REGULATORS
FRONT OF MCV IMG_2355 by richard heydecker , on Flickr REAR OF MCV IMG_2354 by richard heydecker , on Flickr Couldnt find a tag for the MCV, but you can see the sensors front and rear.
Also found a directional valve which I beleive would be the travel speed switch, its busted of course..... tried to look up a replacement but no-go so far but search has just begun. IMG_2342 by richard heydecker , on Flickr IMG_2344(1) by richard heydecker , on Flickr
IMG_2272 by richard heydecker , on Flickr
Yeah, the manual that I bought was a rat nest, wasnt exactly my model also, but helped a little bit, the -3 was much more helpful. But the one I got didnt have a hydro schematic which is a shame. And Hyundia isnt much help, I know somewhere there has to be a manual.....just need to find it, maybe a basement of some dealer.....
Good day Rik There appears to be three pressure switch's in the illustration you have posted , I will do some reaserch see if I can find some better information to help out. KR Uffex
Actually there are 4 and I have been going over a parts diagram I found here https://hce-part.com/hyundai/catalog/e:01:c/ It has parts diagrams and part #'s for Hyundai excavators I believe these are the travel switches for the travel alarm because they look to be coming from the foot pedals off the pilot system.
So I found the directional valve switch, good guys over at Yuken, told me the part number wasnt what I saw but under the rest of the paint on the cover plate. Got that sorted out, just need to get it and wire in the travel switch. IMG_2360 by richard heydecker , on Flickr
Good day Rik So far I have followed your links, as the complaint was that the engine falter using the arm, normally both pumps connect when using arm in (Cylinder out) as well as boom raise this is common for those machines also when using the crawlers the demand from the hydraulics is greater than when you use the bucket for example, while this does not explain the arm out situation I believe it is safe to assume that the demand overcomes the engine power available. Without any PWM to compensate I suggest that the engine is the best place to begin service the fuel system if this does not resolve the issue then it may be a question of reducing the power demand from the pump's. If you are interested I can post a regulator animation makes it easier to understand the function. I have asked a connection in the a Hyundai dealer to try and find a wiring diagram so we may help with the electrics this may take a little time as he is working from home. Keep smiling Uffex
Hi Rik Hyundia connection is asking for serial number and year if you can oblige. KR Uffex
1990 robex 280lc , pin (serial #) E1067
so I did work on the fuel system, it wasnt ideal, tank was clean which was a surprise. I added a pusher pump before the lift pump and added another water separator also. The original was bypassed. The fuel filters that were on the motor actually looked like they had been there from the start and what came out of them was nasty, I'm sure they were probably on bypass. Still need to pop test the injectors, and check the lines from the lift pump to the injector pump. But since the drain and filter and upped the line size to 1/2" seems to run a little sweeter. short vid of fuel filters(click on image will send you to flicker where you can see it) IMG_2326 by richard heydecker , on Flickr and a shot of the pusher pump and water seperator IMG_2325 by richard heydecker , on Flickr
Hey sorry to thread jack but I'm looking for a electrical diagram of my 96 Hyundai Robex 200. Hoping someone might be a le to help