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345b throttle stuck at 8

west coast logging · 2024-05-27 12:16

I have a 345b 4ss The engine won't go to 8 with the dial . The monitor receives the signal and shows 10 In service mode I can get the machine to full throttle In manual mode I can make hit full throttle Service mode states dial is good and calibrated The hydraulic restrictions light is on at the arm rest . The boom drops fast inconsistent The travel is also weak /inconsistent I feel like the hydraulic tank restrictions is causing the throttle limit. New filters all around Ran machine for a few hours now problem beside lower throttle Hydraulic filter housing was cold They have what looks to be a priming pump /button on the bottom of hydraulic filters housing I scanned for codes and had a speed sensor issue I repaired wires and set the depth correctly . Rpm is reading correctly No magnet controller installed

Replies3
  1. #1skyking12024-05-27 14:27

    some of the pros would like the complete serial number to help. maybe the 4ss is enough I don't know.

  2. #2Mobiltech2024-05-27 18:08

    If the light is on that means that it’s not building pressure in the hydraulic tank and that will keep it from going in to full throttle. It uses boost pressure through a line from the turbo to a pressure regulator to pressure the tank up. Check the lines and make sure the cap isn’t leaking air. I think it’s around 7 psi it should build. You will have to work it a bit to get the boost pressure up.

  3. #3west coast logging2024-05-28 22:21

    Yes problem was solved bad check valve and regulator to the hydraulic tank Engine was sucking pressure from tank creating a vaccum and turning the switch on . Also had bad wiring at the speed sensor and a leaking Quad handle that covered the cab controller in hydraulic for a year or so . I found the section in the manual that states it will limit throttle to 1800 rpm 12psi +- 1psi There is a breather on hydraulic tank that can get clogged open or close depending on the environment. Check valve after regulator. Before pressure switch seemed to be the main issue . I disconnected the switch as it normally open and all is could until the check valve arrives Thanks alot for the help. Ended up RTFM alot and found that small write up on throttle limit .