McCoy Diesel Vintage Radio Control (RC)/Control Line Model Airplane Engine

This engine seems locked up
DISCLAIMER: I inherited a vintage model airplane engine collection from my late father. Over the course of over 60+ years of collecting, he amassed a collection of several thousand vintage engines. I don’t have the time or knowledge to give a detailed listing for each engine regarding history of usage, or current condition. What I can say is that these engines have been in storage boxes for the past 5 years, and in a display case for about 25 years prior to that. I am guessing most were heavily used at one time, then retired to display. I MAKE NO GUARANTEES, I.E. if you are looking for an engine to run with minimal time or repair, I would encourage you to please not bid on these engines. If you are looking for an engine for display purposes, parts, or a project, then these engines are probably suitable.
Thank You.