When the left lever is held down, the snowblower doesn't want to move ahead. It worked fine last season and the beginning of this season. Then, it seemed to sometimes engage, sometimes not. Not it will barely move. If I tip the snowblower up a little, it will sometimes help it move. It also seems to engage more often when it's going downhill. Ugh! The attached pics are of a 33" Yard King, so it looks very similar to my 8/27 model ...