Hitachi ex200 hydraulic/engine problem

[kj.fahey]

Update!

I changed the Pump controller behind the seat and the excavator is still doing the same as before

Can use away and idle the machine up and down through the idle modes but as soon as I pump heavy load on machine (like Curling the bucket in all the way) the machine dies

Every sensor out on the pump is new as well as the module it self


The step (throttle) motor is also new

I’m at my wits end I don’t know what else to do besides take the pump off

 

[kj.fahey]

Does anyone know what these relays are for?

 

[Diesel Dave]

Does anyone know what these relays are for?

KJ , check your messages.

 

[kj.fahey]

Can @Diesel Dave or @mg2361 help me out

Changed my pump controller
Changed all sensors out on pump
Angle sensor getting the correct 4.4 volts as well as everything else getting proper voltage
Pump was tested and it’s not the Pump

But my two solenoids that stroke and destroke the pump both have power on them all the time, isn’t one suppose to get power when doing the stroke and one gets power when destroking the pump?

I can unplug one of the solenoids and the machine will idle up fine and will just let the hydraulics operate slow but as soon as I plug it back in the machine starts to overload the pump

I’m in the dark here

 

[3D1]

I had the same thing happen . I was working on a steep slope and ran until the fuel light came on. It must of cleaned all the junk off the bottom of the tank.

I was done on that job and I could barely get it loaded on the trailer. I changed the fuel filters and it went right back to normal. I also had black smoke.

 

[mg2361]

Like he ^^^^said. Engine issues have not been addressed on this thread. Has engine issues been eliminated. Boost pressure? Fuel pressure?

But my two solenoids that stroke and destroke the pump both have power on them all the time, isn’t one suppose to get power when doing the stroke and one gets power when destroking the pump?

While I am not familiar with the EX200, and if those solenoids are like the ones in an EX120, then they have constant voltage to them as soon as the key is cycled on, and the controller supplies the ground to activate them. When they are activated, they are only activated for an extremely short time, just enough the stroke the pump to where it needs to be. There is a test harness from Hitachi (p/n 4283614) that gets placed into the circuit. When running the machine, the light should flicker as the solenoids get commanded.

I can unplug one of the solenoids and the machine will idle up fine and will just let the hydraulics operate slow but as soon as I plug it back in the machine starts to overload the pump

If the ground wire for that solenoid has a short to a ground before it gets to the controller, it can cause that. Test that wire for a short to ground with the solenoid and the PVC unplugged.

 

[Diesel Dave]

While looking at possible engine issues , Check for a plugged screen in the fuel inlet line banjo bolt on the fuel transfer pump.

 

[kj.fahey]

All engine issues was checked