Wanting to add a hydraulic thumb to my 321c LCR. I have plumbing already but it is only one way flow with a foot pedal for a breaker. Wanting to change to 2 way flow to add a hydro thumb. Trying to do research to figure out where I need to start to do this conversion but coming up short. MCF00969 is serial number. I would prefer to switch joysticks out and have the thumb rocker switch to control aux attachments but not a necessity. Pic of the machine below. Thanks in advance for any knowledge, leads, etc
Your current setup have Single-acting aux circuit with foot pedal: Pressure out, tank return (breaker setup), for thumb you need: Double-acting aux circuit: Pressure to extend AND retract cylinder independently. & Joystick or switch control (not foot pedal) Your options: 1: Add/upgrade aux valve section: Install dual-acting aux spool in your existing valve block OR add standalone auxiliary valve. Cat may offer retrofit kit for 321C to add proper aux control - check with dealer using your serial MCF00969. It requires: new valve section, pilot lines, joystick with aux rocker switch (part of Cat "advanced control" joystick) 2: Aftermarket auxiliary valve: Bolt-on dual-spool aux valve (brands: Prince, Cross, Husco) with electric or pilot control. Tap into existing aux pressure/return lines. Add switch to joystick or console. Cheaper but less integrated than OEM Joystick upgrade : Cat 321C advanced joysticks with aux rocker switches are available - check part compatibility for your serial. May require wiring harness changes if switching from foot pedal to joystick control Verify: Verify your existing aux flow and pressure specs (typically 12-15 GPM, 3000-3500 psi for thumbs) - breaker circuits are one of the function which runs on higher pressure/lower flow. Call Cat parts with serial MCF00969, ask for "auxiliary hydraulic upgrade kit for thumb attachment" - they'll tell you exact parts needed. Budget $1500-3000 for OEM conversion or $800-1500 aftermarket.
Thank you very much for this answer. I have some mechanics working on this as well and will pass over this useful info. Been trying to do some google research for days but not getting anywhere thank you again