CAT D5C series III left track in reverse

[Slim Tech]

Car D5C left tankt is stuck in reverse. I capped off line F on the pilot joystick to make sure it wasn't just bypassing inside the valve. Removed the top cover on the front pump, according to sis this is where the actuator is, actuator was stuck in what would be the reverse position, encouraged it back down with a 3lb hammer, ball peen wouldn't budge it. Blew air through line F and made sure it would move up and down. Reassembled and still doing the same thing, left track stuck in reverse, right track moves propero with the joystick.

Replaced hydraulic filters and cut them open, SMALL amount of brass, not much at all, looked like normal wear, nothing like a pump/motor failure by any means. Any other thoughts? I've not run into this before, I have SIS abd looked through the schematic, it all seems to point to the actuator, do I need to go ahead and take it out? Several things need to be removed is why I haven't pulled it yet.

Tia!

 

[Dave Neubert]

I don't think a D5C is hydrostatic it should power shift with torque converter

 

[Mark250]

I don't think a D5C is hydrostatic it should power shift with torque converter

About Half the series 111 range is power shift and the rest is hydrostatic. The only way that the track can move is if the pump is upstroked .For that to happen there would have to be pilot oil on one side of the over center actuator or the pump actuator is jammed up and has not returned to the neutral position or the centring adjustment has some how been altered
Mark

 

[Dave Neubert]

I agree with Mark you need to look at the pump

 

[Tractorguy]

After freeing actuator you said it stuck again, seems as though you’re on the right track may Have to start digging in.