Does anyone know anything about the DR.EX scanner for the Hitachi 120-2. I see them on ebay but the dealer told me they only sold them to dealers not the public. all the manuals talk about them and I would love to get one.
I retired in 2014 but the one thing i remember about ZX was the palm pilot battery. Did not last very long. Had to have connected to a charger to get anything done. But i am sure the newer ones are a lot better they worked good for a cheap scanner.
Steve thanks for the info on scanner, my biggest concern is that I have to order it on eBay and don’t know if it’s the same thing you used. I am at the point of trying anything
What's going on with your excavator. A word of caution, i thank your unit has a four-pin connector for the diagnostic connector. Make sure one of those pins has 5 volts with key on if not none of the diagnostic devices will connect to the controller.
I purchased a 1992 Hitachi EX120-2 and am overheating after about an hour. I have took radiator out and blew it out plus oil cooler replaced thermostat and water pump and I have seen a lot of posts about the electrical and hydraulics causing this too. I also don’t feel it has digging power or the boom and tracks don’t have the power they should. I am not a mechanic or electrician but all the manuals I see talk about this scanner. Thanks for any help anyone. Dave
Did you inspect tubes in radiator for being plugged provided there is not a baffle blocking your view? Does the engine seem to be lugging excessively when operating hydraulics?
I removed the radiator but not the oil cooler I blew out all the fins and flushed the radiator out. The engine seems to run fine but the boom will start to slow down raising and the arm is weak pulling in and you have to raise the tracks with the arm to try and turn it I used an infrared temperature gun and when the engine temperature got to the top of the white part of gauge I shut it down. The manual says it should be about 215 degrees so I checked the thermostat housing it was about 200 all the cylinders were around this temperature and the oil cooler and side of hydraulic tank were 200 plus
So hydraulic functions slow down after heated up correct? If you have someone that can operate for you scan the hydraulic pumps to see if they start heating up pretty fast.Compared to other parts. Make sure hydraulic reservoir is not over full way above top of sight glass. How many hours on your machine?
Hello Steve, I went and looked at the EC module behind the seat and it has a red light that blinks I guess telling you it is on. I noticed the module under it is not even plugged in, I think this is the PVC module. You mentioned a plug is that the plug to the EC module or something else? I am not sure on hours but probably 8 or 9 thousand.
The bottom controller is the pump and valve controller, my guess it was unplugged because it has a short or wiring harness issue. A scanner will not connect with this unplugged. Look at fuses if cover is still on fuse penal it may have a decal on back that lists fuses. Going to grandsons ball game be back tonight. With PVC unplugged you have no control on engine pull-down so engine is lugging excessively.
OKay can I check it out to see if it works or do I get a new one. I metered the fuses this morning by testing on the outside poest for fuses and they all read around 53 volts. I don't feel like the engine is loaded down
Do you mean 23 volts instead of53?
No I was getting 53 volts but I am not an electrician so I might have messed up something I also don’t know what fuse goes to the module
Your excavator electrical is a 24-volt system. Looking in your fuse panel do you see any one amp fuses and how many?
With the PVC module found being unplugged and the engine not lugging excessively I’m thinking there is a “Hydraulic Conversion Kit“ installed on the machine.
Diesel Dave is correct when the pump and valve controller has a blown fuse or burnt up the engine lugs excessively.
These are my fuses and cover plus what the manual shows
How would I know if there is a conversion kit? The machine operates fine but gets hot and seems weak to me
From what I see from posts purchasing A scanner would be a waste of money, What I have seen when fuses are replaced with higher amps you usually end up with fried controller from shorts usually in wiring harness. Pump and valve controllers-have a 1 amp fuse. I have heard of the conversion kits but never installed one. Maybe Diesel Dave can give more info on this.
I’ve never installed a kit either but I know that one step of the kit install removes the (2) displacement solenoids from the top of the hydraulic pump. The solenoids are replaced by a hose and an adapter plate in each location. dcar, Post a picture of the top of the hydraulic pump.
I have found that the PVC is not plugged in and when I plugged it in it does not light up. I will send pic of pump.
Diesel Dave, would it be worth removing the oil cooler to see if it is plugged? the fins are very clean.
Assuming your infrared temp gun is accurate . Sounds to me like your engine AND hydraulics are both running hot. I would check air flow through the rad and oil cooler, maybe the fan is installed backwards. Check all the foam sealing strips are in place on the top, bottom and sides of the rad and oil cooler. IIRC correctly the normal temp differential between top and bottom tanks on a Deere “E“ series excavator radiator was about 12-15 degrees F.
Per your pics of the hydraulic pump,there is a hydraulic conversion kit installed on the machine.
Thanks Dave, should I leave it this way or get a new PVC module and try to make it the way it is supposed to be? I wonder if something was wrong with the wiring. The engine runs great so I don’t think the engine is causing the heat
I don’t pretend to be an expert on any of these Deere/Hitachi machines that have had hydraulic pump conversion kits installed . I think I would start a new thread asking other Deere / Hitachi owners who have experience with hydraulic pump conversions if hydraulic overheating is a common issue.
I remember a problem I had with a EX550 years ago. There is a thermostat in the oil cooler lines that caused me headaches it blocks some oil from going thru oil cooler when oil is cold. I checked parts diagram and your machine has one to. It is item 34 on the parts diagram I am sending. They call it a hydraulic flow control valve but it is a spring loaded thermostat It may be good but worth checking out.
Meant to mention the one i had the spring and nut were in the hydraulic reservoir and the disk was logged in the cooler line. Had to drive it out.
Thanks Steve I will check it out
I have replaced all the fuses with the correct ones and plugged the OTHER PVC Module in and the 10A fuse that was labeled “option “ blew immediately the PVC never had a light come on
Hi Steve I replaced all the fuses with the correct ones, I plugged the pvc module in and when I turned on the key the fuse #19 10A blew immediatley, it says option on cover. The pvc never had a light come on
I would say PVC is fried and you may also have wiring harness issues. The bypass kit was installed for a reason those pump control solenoids also could have fried your PVC. My guess the kit takes you back a couple generations and utilizes Pilot Oil pressure to stroke pumps. It would be great if someone on this Forum has delt with this or might could help you find some installation instructions so engine pulldown etc. pump delivery could be adjusted and checked out.