Just installed a new system, and everything looks to be running well, EXCEPT that 5 or 6 of the Orbit sprinkler heads are leaking a significant amount of water out of the base of the pop-up stem (where it meets the main sprinkler head) when the system is in operation. Seems odd that half of the sprinkler heads are having this same problem. Bad batch of sprinkler heads, or is the problem based elsewhere?
