hitachi ex120-3

[dodgeram22871]

hi all i have an ex120-3 that the all movements are gone slow i checked the angle sensor the 2 solinoids on top of the pump there is 95000 hrs up on the pump has anybody any ideas
thanks for reading this posting

 

[jaytech]

hey dodge
i'm not one the experts but i do have an ex120-2 and i had a similar prob.
first of all you need to go into much more detail on how you checked those components.

i would start with the solenoids.
mark one as left and the other right then mark the left wireing harness connector as left.
now swap the harness connectors to the other solenoid. this is a temporary test. run the mach for a couple of minutes if your computer is actively driveing your pump to min swash it will now be sending you to max swash.
thats probably not the problem but it was a free and easy check.
next test is to swap solenoids (relieve hyrd pressure first).
left harness connector to solenoid in left position.
if neither test changes symtoms its probably the angle sensor (about $500us).

 

[dodgeram22871]

hey jaytech, thanks for that i changed around the 2 loom3 it improverd a small bit also checked the angle sensor i hav 5volts going in but the only way i can 4.5 volts out if i take out the allen studs and turn a good bit nearly 3/4 of a turn

 

[jaytech]

if your angle sensor worked for years and now doesn't it needs to be replaced not adjusted.

when you remove the solenoids the swash plate moves a little toward mid swash (springs?) you'll notice oil bubbleing out of one solenoid mounts.
thats the small improvement you saw. sounds like the pump is ok

 

[rgl726]

you need dr zx. to diagnose you problem.

my suspect is bad angle sensor.

do not adjust your angle sensor there is a setting to do it.

https://www.heavyequipmentforums.co...em-Help-Please&p=186591&highlight=#post186591

 

[dodgeram22871]

hi all thanks all for the info i went to it today, i have 5volts in but 4.97 volts out and when you move the shaft nothing happens so i will order a new one

 

[nucleus]

i'm having the same problem, can anyone please send me the wiring diagram for ex120-3
my email address is v0ltreg@gmail.com, the second character is zero

tia