Tom, they backflush your spray bars, I fill the livewells with a garden hose and turn on the pumps (aerator and recirc), open those valves. It will clean out your spray bars. If you live up in the cold country like I do, you need to open them up and make sure they’re drained before you put it up for winter. I blew a line in my ’09 PIV when water was still sitting in a low spot in one of them.
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