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Hitachi ZX350 Hydraulic thump opens , won't close.

trip

Active Member
Joined
May 15, 2010
Messages
36
Location
Northwest
Hello everyone, I had a perfect working ZX350 lc3 that got a hole in the A/C evap which is under the seat. Removed seat, rear partial shelf, uplugged many wires (after I marked them) replaced evap and put back together.
Problem, everything works except Hyd thumb close. This is located on R/S hand grip with two buttons. Left =open and Right = close. When I switched the plugs by my lower right elbow the Right was now = open. I think that that tells me that the button are OK.

There is a relay panel behing the seat with 4 blue relays. the two on the right (looking towards rear of machine) I think go to open/close buttons. When I push open does open) L relay clicks and all works great, when I push R/S button R relay clicks but no close. I am assuming that I have power to relay if it clicks???

Thought that the problem was then between wires going out of relay andand out of cab.

I was going to start looking "down the line outside of the cab but I still think its something in cab because it worked fine 4 hours earlier and only unplugged and replugged. Any thought would be appreciated, thanks!
 

GaryHoff

Senior Member
Joined
Feb 25, 2009
Messages
810
Location
Alberta, Canada
Occupation
Heavey Equipment Mechanic
Did you do the simple checks first? Fuses are all ok? You have the auxiliary hydraulics in sheer (bi-directional) mode? (breaker mode only gives you flow in one direction)

Behind the seat the there is a 3 pin connector SR/H, for the right handle. It may be poked out a little ways through the cab hole. Check the connector for power when you push the buttons on the right joystick. ( black wire is ground, other wires are switched power from joystick ) If you have power, then check the diodes for the auxiliary solenoids, which should be on the frame behind the cab.
 
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