This Briggs & Stratton chart will answer your question. http://www4.briggsandstratton.com/miscpdfs/RNT/Engine%20Specifications%20Chart_ms3992.pdf

I have a bs ohv ,6 hp on mtd tiller, problems, govenor does not work, engine runs at highspeed all time, also the pull rope is very hard to pull and will not spin the ingine