Check your calculation using the example below. Note the selected gear and throttle setting used during the speed check. Record the tachometer reading for use in setting the throttle during operation. You find it takes 19.5 seconds to drive one way and 20.5 seconds to drive the other way, an average of 20 seconds. It is normal for the tachometer or speed display to indicate speeds greater than 6 mph due to wheel slip.
Wheel slip can be substantial under heavy drawbar loads.
You should collect a volume of spray no less than 37 ounces and no greater than 41 ounces in 1 minute. Use the manufacturer's information to estimate the operating pressure required to achieve the desired flow rate for the selected nozzle. Measure nozzle flow rate To perform the following test, the sprayer must be operated at constant pressure. Use a graduated container large enough to hold the spray produced by one nozzle in more than 1 minute at the selected operating pressure. Place the empty container under a nozzle and collect all of the spray for exactly 1 minute.