See the hydraulic schematic I posted above. The two small external lines are for travel motor case drain and two-speed. There is no travel motor brake the way we understand it. Same comment still applies though - are the two lines somehow mixed up.?
I found another thread where the OP was asking about the location of the case drain & 2-speed lines at the swivel. I suggest that before going anywhere near the main hydraulic control valve the connections of those two lines between the swivel and the travel motor that is not performing need to be investigated. Also this comment in Post #2 from the OP above -
"Also, two-speed does not seem to be working." It could be that a single cause is at the root of both problems.
https://www.heavyequipmentforums.co...dentifying-drive-motor-hydraulic-lines.95929/
I've followed the case drain line and the 2-speed line from the drive motor to the swivel, and they appear to be connected in the correct places. They mirror the connections of the drive that is working correctly. The 2-speed line isn't getting pressure (on either side) because the 2-speed is not working. At this point, I'm not sure if it's the foot switch you step on or something more involved. I'll try to dig into that today.
Just for clarification, this machine does NOT have a standalone brake line on the drive motors. The drives do have brakes, but they're released as pressure builds in the forward/reverse drive lines. When the drive lines get pressure, the brake is released and the drive starts turning all in one action. This is according to the service manual. I don't believe the issue is with the brake since the drive works fine on the other side of the machine.
I disconnected the case drain line from the problem drive and ran it forward/reverse to see what would happen. I do get some fluid coming out of the case drain port on the drive. Nothing crazy, just think of pouring out a 12-ounce can of Coke. That's as the drive is slowly turning and the machine is bogged down. The place I bought the drive from suggested blowing compressed air into the case drain line to clear any blockages, but I don't see how that could be the issue.
With the drive getting 3,800 psi but the machine struggling to turn it, could this be a flow issue versus a pressure issue? In other words, the drive is getting enough pressure, but not enough flow. Maybe a blockage or a valve that is not opening fully? I've just about hit the limits of my knowledge of hydraulic systems.