Are they the side to side levers? Back at that time I believe TH Marine supplied most livewell parts. Before changing everything there are a few things to try that might fix your issue. First take out the levers and disconnect the cables. If the levers move freely that's one issue down. Next and it's usually a pain to do, get down in the bilge and disconnect the cables from the valves. In the cable moves freely back and forth, the valves are most likely the issue. You can try moving them by hand but if everything else checked out OK, they will probably be stiff. Depending on what each valve actually controls, if they are the TH Marine style (usually white or black) there should be 4 screws holding it together. Take out those screws (careful not to drop they are tiny) take of the cover and you may find a bunch of crud in there preventing them from moving. Clean them out and put it together, they should move freely now. If all that works , you should be good to go.
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