Hi, Folks.
Here is a video of an Inertia starter system being used to start an Ansaldo TCA70 crawler, a now defunct Italian brand from the 1930s-50s, a few of which found their way DowNunda. This one is in an Italian collector's line-up.



Some WW2 German tanks with Maybach engines also used inertia starters, basically a heavy flywheel which was cranked by hand until it was turning over quite quickly - with a LOTTT of inertia - and then a clutch was engaged to connect that inertial energy to the engine. BRRRRRRMMM - hopefully.

Just my 0.02.

some lawn movers used a similar idea. wind up the spring and then release it. you can still buy them for many applications.