Ok i have a buddys hond gvc160 5.5 pressure washer and i have no idea how to use the chemical injection on it. The instructions on the pressure washer itself say to place injection tube into chemical and set nozzle on low pressure. The nozzle can be twisted for fan and stream. On the other side it has arrows up for low and down for high, but the nozzle does not move. Can some one please help me figure this out?