Tractors with original rope start engines with special air intake are rare and NOS parts to rebuild vintage motors are even rarer.
Common engines included 1-3/4 HP Briggs and Stratton on 'economical' special, without hood and 'rugged' deluxe, with hood. 2-1/4 HP B&S or Continental engines were shipped on 'big husky'' Super Power
Later tractors used B&S 5 HP, Wisconsin 5.6 and Tecumseh Lausen 6 HP engines
Auto type clutch with 6" molded asbestos linings underwent design improvements as HP increased