Hi. I created this account in order to post to this thread and thank you so much for the info on the worm gear eccentric and how to adjust it. I have owned this same table saw since 2014 and for the last few years have run into that same problem; except, in my case, the pinion gear slips off the rack right before I tilt my blade back to 90 degrees. Although it was quite clear that the pinion and the rack were not aligned, I could not figure out how I could adjust either one to bring them back into alignment until I found your lumberjocks post, which fortunately came up at the top of google when searching for "ridgid table saw slips when blade tilted to 90 degrees."
The 14mm "nut" was at first difficult to move, but for me, it moved easily after spraying the area with some penetrating oil. After that, I was able to move the pinion enough to where the blade can now tilt a bit past 90 and a bit past 45. When looking at the gear from the cabinet door, the pinion still seems too far to the right of the rack, but it works good enough.
Overall I like the table saw, and have gotten good use out of it over the last 8 years. It is quiet, vibrates little, cuts well with a sharp blade, and is accurate and adjustable. Of course it has no problem with rust, although I guess you lose the benefit of magnetic jigs. The only real thing I don't like is that the front and rear rails come in two parts, which makes aligning the fence difficult, so I just replaced the stock rails with a single stretch of square tube/angle iron. Aside from the rails, I replaced the arbor as well as the motor bearings, and I ditched the stock splitter for an aftermarket riving knife (from where I forget).
So thank you once again for figuring that out and posting it to the internet. It solved a problem that had been vexing me for years and it spared me countless hours of hopelessly fiddling around with the saw. Much appreciated!!
