Now that I know what to look for, I inspected the fuel lines on the Puppeteer and found what I believe is the problem. The Puppeteer is constructed differently from the Legionnaire with no hole in the firewall. Rather the engine tank bay is open to the engine area. So it wasn't a constriction of the tubes passing through the firewall. Instead it looks like the fuel line got "kinked" like a garden hose and thus the same ultimate effect as on the Legionnaire. By clipping off a 1/2 inch of tubing made this unlikely to happen again.

Odd that such similar problems would crop up on two models at the same time. Probably speaks to poor plumbing skills.