Replaced the waterpump in 70hp chrysler. The old impeller had 12 fins. The new impeller has only 6 but are twice as long as the old one. Was told that more fins = more presure. Less longer fins more volume. 12 fin impeller will fit new housing. Using new impeller. Which is better more presure or volume? Water doesn't spray from moter leg at full throttle. It runs out slowly and surges pretty good about once a second. Does nothing at 3/4 throttle but doesn't seem to get hot. Problem getting better. Just doesn't seem quite right yet. <br />Prev. owner doesn't remember how much or how water exited the leg.
