Good luck in finding any info on that engine. Looks like one of the clones MTD is using, of which there is very little info out there. When these come into the shop, the only way we get specs is the go to our distributor and hope they have the info. This is the main reason most techs put the in the one use and done category. Also the reason they sell so cheap.
i have a yard machine mower and on the engine(powermore 140cc) theres a sticker with valve lash, plug gap and other info on it.. look for that.. on mine, 0.010mm intake and 0.015mm exhaust is the spec.. whatever that tranlates to in standard..