I have several sprinklers (photo link below). They have two kinds of
problem. Some of them, after having spinning for months, suddenly stop
spinning. They stay at a fixed position and flood the place where the
nozzle is pointing to. This happens when the sprinkler is set to spin
360 degree. I'm not sure if this has anything to do with water pressure.
The other problem is that when the sprinkler is set to spin for a
certain degree, say, 180, it would spin to one end and be stuck there.
It is supposed to spin to one end, reverse and return to the other end,
back and forth indefinitely. But no. It would not reverse. How exactly
does the reverse mechanism work? I can' figure it out. The downward clip
is flipped, which, if works normally, should somehow make the sprinkler
reverse its direction. Some of the sprinklers just would not reverse. If
I manually turn the sprinkler to the other end and release it. It would
spin to the same end and be stuck there, though the downward clip is
flipped.

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