My grizz 700 was just purchased. I noticed once I got home that from stand still in high and low you have to rev motor a good bit before it actually takes off strong. Under a light load it feels like it tries to pull but not feels like a brakes holding it back. I do not smell rubber from the housing snorkled and I just serviced the primary thinking that was the issue. When you put it in reverse it goes fine. With no slipping feeling. Any suggestions?