never seen this starter mechanism before,what engine is it?

By the size of the needle valve I'd say it's one of the later non anodized Pee Wee 020's. Or it could be your use of a wide angle lens that's making it look larger than the rest of the engine. But if you provide us with a measurement of the overall length from the drive washer face to the backplate we could answer a lot easier.

Definitely a Pee Wee .020 with a spring starter and a ribbed prop nut for the soft plastic spinner. I've never seen one with that disc looking gizmo up front...perhaps a flywheel or a friction drive disc?? Beats the heck outta me Lieutenant! Uhh, Leftenant for yuse Canucks and Limeys.

it's an 049 but the starter has me stumped,it is a recoil starter like the one on a testors mccoy.

Oops, OK an .049 then. The relative size of the fuel nipples and the needle valve fooled me. Looked like a Pee Wee.

If it's a recoil starter the engine maybe came off of a Cox RTR car and the spinner nut doesn't belong on that engine. (?) Dunno why it has both a spring starter and a recoil starter.

I think thats the flywheel thing under the plastic screw gear that came on the dune buggy/baja bugs...but the prop nut-spinner mount is from another motor....Rog

Little known trivia: Cox did make a Pee Wee .020 with a flywhell and gear for use in their cars. I happen to have one but it looks nothing like the one in the pic.

First generation surestart starter?

Excellent!

For real question: How did the starter engage on this engine?

George