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Komatsu 1997 pw130-6, stalling randomly with black smoke

jth · 2016-11-05 06:38

Hello, I have some problem with this machine. After one hour of use it starts to stall in heavy load. It does not do that every time but randomly it does. If joystick is relased little, rpms raise back. When this happens, it sounds like motor is pumping up and down because pump is changing load. Like it first doing right and then takes too much load. Still rpm is going down and finally stalling motor. I have been checking monitoring code 11 (pump discharge pressure input) when this happens, thinking that it stalls because of heavy pressure. It looks like the pressure is something between 150-325. Sometimes that happens if you drive cylinder to end position. Thanks

Replies2
  1. #1dogcyber2016-11-06 12:51

    Any error codes? how's your air filter? How's your boost pressure, any leaks? Have you tried the machine in pump override mode? TVC solenoid?

  2. #2jth2016-11-07 03:28

    No error codes anymore. There was a wiring problem with TVC solenoid, error code for it. Wires were working ok with cold machine. After warming up, stalled very easy. After replacing new wires, problem is not any so big any more. It still is hard to do some fine work with this machine, because you need to follow rpm. I was thinking is there some another important almost broken wires in same cable set which make same effect, like epc valve wiring? Air filter is new, haven’t check turbo pressure (if boost pressure is that) and motor runs ok. Banjo filters are checked and fuel line also. Override mode gives same effect. It looks like previous owner has made adjustment for tvc valve and ls-valve. Still, machine runs very well for first hour, after that it starts to be too fast and randomly want to stall