The only reason I could see for the clutch was I would use it to stop the Rototiller It stops all action out of the engine Via drive shaft; I had/rebuilt 7 in my collection and it seams there was small differances on them Yet they were all the same. And in my humble opion They were the best and truely the first garden thector. There only bad point was No power steering. and you put a bucket or blade on it it was hard to steer. Other then that. #1. I sold one a while ago for $3850.00 That is more then they sold for new, Of 7 i still have 1 left it's a work horse. Tiller. bucket. Deck, Blade. Life is so good..