Hitachi EX120

Bighead · Sep 24, 2020

Machine has been sitting a year. Went to it today. And machine will run perfect at any RPM. Tracking works properly. But any boom function or swing function and the machine will choke down and almost cut off before it will preform that function. Any ideas?

mg2361 · Sep 25, 2020

Just boom and swing? What about bucket or arm functions?

What dash machine is it (-2,-3)?

Bighead · Sep 25, 2020

mg2361 said:
Just boom and swing? What about bucket or arm functions?

What dash machine is it (-2,-3)?

Any boom or bucket functions and hydraulic thumb will die the machine down and I believe it’s a -2

mg2361 · Sep 25, 2020

First thing I would check on those machines are the fuses - F3 5A EC Motor fuse, F4 1A Valve backup fuse, F7 1A Valve controller fuse, F8 5A Solenoid 1 fuse and F9 5A Solenoid 2 fuse. Especially the F4 1A.

You said the tracks work fine? They don't want to stall the machine too?

Bighead · Sep 25, 2020

mg2361 said:
First thing I would check on those machines are the fuses - F3 5A EC Motor fuse, F4 1A Valve backup fuse, F7 1A Valve controller fuse, F8 5A Solenoid 1 fuse and F9 5A Solenoid 2 fuse. Especially the F4 1A.

You said the tracks work fine? They don't want to stall the machine too?

No. Tracks work just as they should. We managed to load the machine on a truck and get it off the truck just fine. But no other hydro function

mg2361 · Sep 26, 2020

Fuses good?

If you have 24 V to your pump control solenoids try swapping the solenoid assemblies (make sure wiring stays in the same relative location, wires for solenoid closest to the engine stays closest to the engine) to see if your hydraulic issue changes to slow/weak hydraulics.

Hitachi EX120

Bighead

Member

mg2361

Senior Member

Bighead

Member

mg2361

Senior Member

Bighead

Member

mg2361

Senior Member