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Hitachi EX330LC-5 hydraulic problems

Sloaner250

Member
Joined
Sep 15, 2020
Messages
5
Location
united states
i am working on a hitachi 330 ex330lc-5 currently the machine has all but lost right side joystick and track functions, hooked up gauges to pumps and left pump reads 4,000 psi when moving functions, right side pump reads 1,500 psi when moving functions then tested the pilot signal lines to top of both pumps and left line reads 275 psi and right side reads 450 psi. i then swapped the pilot lines around on the pumps because i thought maybe the diffrence in pressure was causing one pump not to stroke up but switching them didnt change anything. anybody have any ideas?
 

uffex

Senior Member
Joined
Jan 23, 2012
Messages
4,464
Location
Lincoln UK
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Admin
Good day
I suggest you check out if the right side joy stick has pilot pressure, check if those lost functions come back when you dead end the arm.
Kind regards
Uffex
 

Sloaner250

Member
Joined
Sep 15, 2020
Messages
5
Location
united states
Good day
I suggest you check out if the right side joy stick has pilot pressure, check if those lost functions come back when you dead end the arm.
Kind regards
Uffex
I have tried dead heading the stick cylinder and it didn’t change anything, I have pilot pressure on the right side joystick because the functions still work they just hardly move with no power to do anything
 

uffex

Senior Member
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Jan 23, 2012
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Location
Lincoln UK
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Admin
Good day
The result suggests there may be an issue with P1 pump regulator - has anything been disturbed recently or any history that may give some cause?
Kind regards
Uffex
 

Sloaner250

Member
Joined
Sep 15, 2020
Messages
5
Location
united states
Good day
The result suggests there may be an issue with P1 pump regulator - has anything been disturbed recently or any history that may give some cause?
Kind regards
Uffex
Unfortunately no nothing has been disturbed or messed with recently. I’m gonna pull the regulator off and tear it down anything Specific I should look for?
 

uffex

Senior Member
Joined
Jan 23, 2012
Messages
4,464
Location
Lincoln UK
Occupation
Admin
Good day
I would e looking for a sticking spool may be switch it with the other pump.
KR
Uffex
 

Sloaner250

Member
Joined
Sep 15, 2020
Messages
5
Location
united states
okay today i pulled regulators off of top of each pump and switched them and it changed nothing. anybody have any ideas? im kinda thinking its the pump.
 
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