The Stovebolt Site Forums The Shop Area Engine Shop GMC 9430 engine troubles

I figured out the problem. I expect others might some day face the same thing so I thought I would share the experience.

I removed the starter to find a major mouse house inside the bell housing surrounding the flywheel. The vent ports on the housing are the perfect size for them to get in. This is where most of my bench seat ended up after the mice got to it, haha. I removed the little pan on the housing and sucked it out with the vacuum. Side note: If anyone knows the part name of this pan please let me know as I need a new one.

What was preventing the starter from disengaging was some of the seat fibers were impacted between the teeth of the ring gear. Amazingly this was enough to prevent the ring gear and starter gear from meshing properly, which caused the engine to stick when turned. I dug out all the fibers and cleaned up the ring gear and it all rolls smoothly with the starter lever engaged.