• Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!

terex mini Ex dealer can't figure out .. what to do next ?

BobbyL

New Member
Joined
May 30, 2016
Messages
3
Location
wv
My dealer has been on phone with terex and they can't figure out whats going on . I have a hr-16 terex 8000 lb mini 1400 hours . All controls operate fine for 10 to 15 minutes then it gets jerky . when swinging boom side its a little noisy too . All controls still work , pressures stay right on where they should . Pump has been off and inspected and all good . They say I needed a relief valve got it , no different . Then check valve , got one , no different . Anybody with any suggestions please respond . Been at dealer 10 weeks
 

Huntoon

Senior Member
Joined
Mar 14, 2012
Messages
265
Location
California
Occupation
Sales Engineer. I design OEM tracked undercarriage
Any chance of inline counterbalance valves being contaminated? If they have them?
 

jcb jeff

Senior Member
Joined
Nov 23, 2014
Messages
394
Location
United Kingdom
Not familar with the brand but sounds a bit like servo pressure to high or you have a restriction in the tank line may be from the servo/pilot levers back to tank when its getting warm .
Has it got aux or breaker on the machine thats not stuck slightly open sticking pedal ect causing a flow divert.
Possible crack in the servo maintenance valve when warm
Also what is the condition of the hyd return filter any bits or blocked ect and has it got the right micron material as sometimes new machines come with a finer micron to collect debris from production until first service .
Personally i would be putting/tapping in gauges in the pilot circuit in various places to see when it gets warm any thing changes may be places like before and after servo maintenance valve in the return circuit and get it hot an see if any thing changes.
If its slew it could be cross line reliefs playing up on the motor if its got a slew brake this could be dragging.
 
Top