I have a Rayco RC-12, John Deere engine, Year 2006 which is missing much of the hydraulic system. I hope to understand it enough to order components and put it back together. The machine is great otherwise, and I would love to see this 80HP monster run. Attached is a diagram that is similar to my setup, but the machine I have has 2 valve blocks, not just 1 combination valve block. I obtained this diagram from Morbark which has acquired Rayco. They believe this is the closest they can get me, and I am now on my own. In particular, I know I will need electrical interfaces with the clutch and feed control bar. I imagine the clutch interface pauses the feed as the RPMs drop. The control bar should also have forward, reverse, and stop. Finally, there are two hydraulic cylinders which raise and lower the feed roller with an Up/Down/Lock control. Please let me know if you can help, or if you can put me in touch with someone that can. Thanks.
Unfortunately all Rayco schematics of that era weren't that reliable so don't bet your house on them. My suggestion is to copy another manufacturers schematics of a similar size machine that is available. Sorry I can't be more positive but still have the burn scars from that outfit.