What type of sprinkler heads do you have, and how old are they? Usually putting any type of lubricant on a sprinkler head is not a good idea, as it can cause premature wear. Sprinkler heads are built so that water acts as a natural lubricant for internal gears and parts of the sprinkler. If you are having problems with the sprinkler heads not popping up or going back into the ground, it is most likely a problem with the seal or the spring (if your water pressure is ok). If they are older sprinkler heads, I would suggest replacing them with new ones.
Tony Posey
Ridge Run Landscapes
