There are no adjustments for pump. Amount of water it will pump is set by pump design. The way I read your posting is the pump picks up prime but not enough delivery. Check your connections (pipes) make sure your not sucking air on any of them. check for obstructions in discharge. Are you sure the water source will handle a pump this size? Its possible also the foot valve is stuck.
Answers & Comments
There are no adjustments for pump. Amount of water it will pump is set by pump design. The way I read your posting is the pump picks up prime but not enough delivery. Check your connections (pipes) make sure your not sucking air on any of them. check for obstructions in discharge. Are you sure the water source will handle a pump this size? Its possible also the foot valve is stuck.