You need to either change where the linkage is mounted or add a counter weight. The head is a teeter totter, think of when you are a kid, if you have a big kid and little kid, you put the big kid forward closer to the fulcrum or pivot. The little kid back, farther away from the fulcrum. You need more length at the motor and less at the head. The torque or "pull" of the motor needs to equal the weight of the head. So you can change the length from the fulcrum, or you can add a counter weight to the motor side to compensate. Weigh the head. You need a counter weight near that weight. Just hang something on it. If this doesn't work, your motor is probably shot. The springs that J-Man is suggesting also works the same as a counterweight. It helps your motor with the load. I have been using my deer motor with my creep for years, it is not that big of a strain, you must have a heavy mask on there. Why not try it with just a foam head and add weight to see where it fails?