Question
I have a Hydrotek 6004, using all four zones. The valve did operate properly when originally installed about 6 years ago. 1 of the four zones will not rotate( unless assisted by tapping the side of valve) have opened valve several times and sanded and cleaned. The zone that does not rotate has three rotor heads on it while the other 3 zones are pop ups? The yard is level and the height of the indexing valve  is above the zone in question. Any ideas? Thanks

Answer
Hey Richard, we don't really install the indexing valves, but normally the insides start wearing out. As long as the heads are spraying water, and they are not clogged up (water moving through the valve) then the difference in heads should not matter. They sell rebuild kits for these, I would suggest getting a kit, and rebuilding it. Good luck and have a great day.