I bought a used Roto Hoe 990-2 to plant my garden at my new house beacuse all the new tillers in my price range looked so cheaply made. The Roto Hoe runs great and the 4 speeds all worked and the tillers blades works however, I tried to till the garden and when it is in gear and you turn on the tiller blade it stalls out. I tried it with just the blades running and it either wants to skip along or if you hold it back the blades won't dig and the belt just slips. Any suggestions? The blades are home made so they are little big I can buy smaller blades but, since it stalls out when I'm in gear and the tiller blades are going theres not much since to put smaller blades on.