The swing brake is nonfunctional causing the house to rotate when digging with side pressure. The dealer says the issue is internal to the drive motor and the parts are NLA. I was hoping it was an electrical issue, but the dealer says the brake is spring applied and hydraulically released when the motor sees pressure. The dealers suggestion is to live with it, but I'm hoping there is another solution. Ok, the parts might not be available from Komatsu, but what about from the motor or gearbox manufacturer? Any other solutions?
I'd check the solenoid is not seized or powered via a short and allowing oil pressure to go to the brake to release it, in other words I'd cap the hose going to the brake and try and slew and see if it moves, I'd also check the safety valves and pull the top off the motor and check the swing brake spring, finally I'd pop the brake pads and dics out and see if they are cooked
Is it possible the motor is locked to keep the house from spinning? I ask because I don't see a brake mechanism.
25 and 24 in the first pic are brake discs and plates. Motor is supposed to hydraulically lock as well, U need to release the brake and put a tap in line and hold the brake off to check for leaks on the control valve side