Hi, I have a uchida valve body off of an airman ax35 that controls the 2 speed and pilot shut off. Both solenoid coils were bad and the wires were cut. I pulled the spool valve out and there were no o rings on the spool, it looked like there was one place in the middle for an o ring but the clearance is very tight where the spool won’t go back in with an o ring. The 2 speed was frozen on and so was the pilot valve so the hydraulics were always live. I freed them, have coils ordered but unsure if that design is an o ring free spoil?
Show pics? Probably just metal on metal sealing
This is the parts break down. It seems likes it’s a metal to metal seal. I was surprised the hydraulics still functioned after I freed the spool and reassembled with the solenoid coil disconnected, it should be resting in the off position. I’ll take a pic of the actual parts later today.
Could be jamming in the housing might need to use some 1000grit on it. Get it all the time with small pilot solenoid spools, I've found generally unless linsihed to take the edge off a bit they jam right back up