Hitachi EX200-3 Pump Stalling Engine

[Rosky]

Hello,

I Have a Older Hitachi machine and I'm trying to figure out whats going on with the pump.

So here's the problem,

On start up you can hear the pump stroke up,
If you try and operate any controls the machine stalls and sometimes shuts off,
the machine wont rev very high at all because of the pump.
sometimes it seems very hard to even start because of the pump.

So I read on some previous thread with people with similar issues on things to try first and so far I managed to check and re calibrate the Angle Sensor to required voltage didn't sense any change in the machine.
I have Volt tested DP Sensor, Solenoids on the pump, Angle sensor and they are all reading the correct volts or very close to it. The pump Computer and main Computer are flashing with no error codes 1 sec on 1 sec off.

I Attempted to try and put it in limp mode but was doing it incorrectly because i didn't have all the details will try again tomorrow. will report my finding if its successful.

EX200-3
14C-78439

 

[John C.]

Sounds like the swash plate has fretted out and the piston and barrel assembly is stuck in the stroked position. How many hours on this unit?

 

[Rosky]

Sounds like the swash plate has fretted out and the piston and barrel assembly is stuck in the stroked position. How many hours on this unit?

the hrs meter is dead on it i would guess about 9000+ hrs

I was able to put it into limp mode to move it around the pump seemed to be fine in limp mode, machine ran but ran as you would expect it to in limp mode.

Is there anyway to really tell if the DP, Angle, High/Low Solenoids are actually bad? without just having to replace them.

 

[excavator]

Start the machine and disconnect the solenoid valves on the top of the pumps. The pump swash angle should slowly change. It should take about 3-4 minutes and you should be able to hear it.

 

[John C.]

If it will work in limp mode I would guess the pumps are probably OK. I think you are going to need someone with the Dr EX to plug in and see what is going on with the electronics. I believe the computers are behind the seat under the plastic cover. See if the diodes are on indicating that there is power to the boxes. You have reaches my limit of knowledge on these machines. Someone will probably be along soon with some pointers.

Good Luck

 

[Rosky]

Start the machine and disconnect the solenoid valves on the top of the pumps. The pump swash angle should slowly change. It should take about 3-4 minutes and you should be able to hear it.

Take it out of limp mode first?

Now that you mention it, I use to hear those solenoids making chattering noise, and now it doesn't anymore at least not while idle when it is not in limp mode.

Both computers are flashing red 1 second on 1 second off, even after I disconnect sensors.

 

[excavator]

Yes you would need to take it out of limp mode.

 

[spitzair]

Could it be that somehow the wires for the solenoids on the pump got crossed so that the #1 solenoid is plugged in to the #2 wire? I've heard of these solenoids going bad, the fellow bought brand new ones from some place in China and they were bad right out of the box. If it's like the 200-2, they should be identical. Id' try swapping them and see what happens, if one is bad and the other is good you should get at least some form of control to your pumps back I would imagine...

 

[Karlukalaska]

ex200-3

Could it be that somehow the wires for the solenoids on the pump got crossed so that the #1 solenoid is plugged in to the #2 wire? I've heard of these solenoids going bad, the fellow bought brand new ones from some place in China and they were bad right out of the box. If it's like the 200-2, they should be identical. Id' try swapping them and see what happens, if one is bad and the other is good you should get at least some form of control to your pumps back I would imagine...

I have this very same machine, last year it started, check your wiring at the pump. Follow each one from each sensor all the way down. I had to peel off the black plastic wrap, the plastic coatings on and in between the wires rots right off, and in places you cant just see, any how I lopped off every connector and soldered some to, got the job done, now in the end, here I am currently getting ready to install a new wire harness to the machine {god help me) lol

 

[Rosky]

Yes you would need to take it out of limp mode.

Didn't hear any change or anything and the machine was still the same.

So I went and bought new DP Sensor, Solenoids, and also an Angle sensor which for some reason wouldn't get to 4.4volts it was reading 3.8-4.2volts but the old one would adjust perfectly to 4.4 volts when moved correctly and the machine still didn't run correctly with the new items and old and new angle sensor and the dot on the sensor was facing away from the harness.

So now I'm stumped, any other ideas that can cause this besides Solenoids, Dp, Angle, Harness, PVC?

I looked for screens on the valve bank near the dp sensor everyone talks about but I have yet to see these screens. I took off the two hex bolts to the right of the dp sensor and its nothing in there.

 

[wilko]

I've had trouble my 120-2, the problem turned out to be where the harness plugged in to the computer. (bottom box, behind the seat) Try jiggling the plug, if memory serves, you'll need a 10 mm wrench.

 

[spitzair]

Rosky, I had the same dilemma years ago wih my EX200-2 and the only solution was to rewire the entire machine. I had spent hours and hours and hundreds of dollars trying to fix the original harness but it was all for naught. The wires can become brittle inside the insulation and break in there and you'd never see it. Had a pickup truck the same vintage and it was having all kinds of wierd electrical issues too, same deal... Once I rewired the machine all the problems went away and it's been running good as new now for the last 5 years. In hind sight I wish I would have rewired the machine right from the start, would have saved many hours of aggravation and frustration. The rewire itself really isn't that bad of a job, it took me about two days from starting to rip the old one out to having the new one in. You can read my thread about it here :
https://www.heavyequipmentforums.co...-Hitachi-EX200-2-computer-question&highlight=

 

[Rosky]

got both computers out and on top everything seems fine but underneath there is like this rust type of residue, anyone know why is that?

I'm going to look into the harness a bit more I knew from the beginning it was a bit suspect but for the most part non of the wires are actually cracking on the harness in most common areas

 

[excavator]

It looks like you might have had some moisture get in there. Like John C. said in an earlier post you really need to find someone with a DR EX that can check codes and functions to really see what is going on. Then, if you indeed do need a new harness you can PM me as I have a brand new still in the box harness from the cab back. I've had it for many years and would love to get rid of it.

 

[Rosky]

Can't find anyone with Dr ex will John Deere service advisor software work? The guy said he could download all different brands of machines.

 

[shopguy]

the solenoids have 24vdc all time the pvc supplies the ground check for that at the destroke solenoid also check the pilot pressure at the pump that is what destrokes the pump
Hope this Helps

 

[excavator]

Rosky, I don't have access to Service Advisor so I can't answer that question.

 

[Rosky]

And over a Year later still working on this 200-3, we installed a new harness, sensors, the works pretty much only thing haven't touched is the pvc, since before, the pump is no longer stalling the engine problem is now the machine won't move at all unless use both pumps but one or the other wont work has to be together, i switched the solenoids around and the problem doesn't change sides.

some ppl say clean the filter on the valve bank but i have no clue where this filter is located or what it looks like if someone can find a mock picture or point me into the right direction I would be thankful.
or if anyone have the slightest clue what may be going on now with this machine.

other issues is the electric motor for the throttle keeps moving and resetting itself when i turn the key on and if i start the machine it goes from full throttle to idle over and over rapidly and i cannot control it. in a different scenario if i unplug it crank the machine and move the arms really quick with the break off and plug it back up it somehow magically works and doesn't do it anymore and the inside I.L.E.P buttons will work again. but the problem eventually comes back.

I installed a new engine stop motor and its not working at all either i have to pull it manually to shut off the machine.

Everything is getting voltage the solenoids are at 24v, angle sensor is set to 4.40v, dp sensor is new and getting volts, pvc and engine controller is flashing as intended, I'm stumped. again please help.

I'm in Houston, Texas cant find dr.ex no dealers even use them anymore.

 

[Rosky]

here are videos that kinda show what its doing shitty footage but i am only one person.

also attached pics of the valve block if anyone can point out where the screen is located that needs to be cleaned and also the main relief valve
https://imgur.com/YTE4IBn
https://imgur.com/cXNidYR
https://imgur.com/eCPKtNE
https://imgur.com/6XeCMII