[dpvu]

I think your sector gear is not engaging the first tooth of the piston gear rack. If you have another cylinder, try that. Check to see if there is any wear on the first tooth of the piston. If the receiver fit isn't proper and the gear slips past the first tooth it VERY quickly wears it down (probably within one or two cycles) and will never engage again. I had a similar issue even on a PTW. Had to replace gear racks twice.