My Hayward northstar pump does not display the GPM. Im trying to figure how long it takes for 1 full turn. Model # is SP4007X10NS. its 1HP...sf 1.40(what ever that is) code j....rpm3450.....27ft from skimmer to pump..2 1/2" pipe from pool to back of pump then it goes from 2" pipe to filteration system. Its a 12,000 gallon pool. Can you help me out?
