RAH:

Is there a place where you can drill/tap in a set screw from the impeller to the shaft? If so, carefully drill the center of the impeller out, and use a gear puller to pull it off the shaft. Replace leaking seal, drill/tap impeller and grind a flat spot on the pump shaft for the set screw to bottom out against.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).