Howdy folks, brand new to the group - I've got a 690C that I'm having trouble with. One track has developed what I'd call a stutter. It moves fine in tandem with the other, but during certain functions like only using that track, or counter rotation of tracks during a turn around, the problem track will move for a short time - which seems to vary - but 5-10 seconds on average, then will slow, and stop. This does not affect the strong track, and is very responsive when moving the same direction in tandem, or when elevated from the ground using the boom to lift the excavator. I've rebuilt the weak track drive motor, finding several seals & backup rings to be in poor condition. No change in function after this repair. The two speed solenoid is not an issue - it is in the correct position and functions properly. The weak track is less prone to the stutter at a working throttle range, but seems to have essentially little to no power at lower throttle ranges. I'm wondering about 1) the brake on this side of the machine - perhaps improper disengagement when the track control is activated is keeping the brake partially engaged/allowing it to partially re-engage or 2) the problem is compounded by a counterbalance valve that is improperly engaging the brake. The drive motor appears strong, it gives me the impression that the motor is encountering resistance and coming to a stop. Anyone have insight on this type of problem, or thoughts on where to go from here? Thanks! -Matt
Have you resealed the swivel?
Dumb that down for me - I'm not following what you mean by reseal the swivel. Thanks!
Your parts and repair manual will refer to it as the rotary manifold, its what transfers hwd oil from the upper structure to the drive motors. Its common for the seals to leak causing issues with travel.