I have a '73 Mastercraft with a 351 Ford Clevland engine that orginally came in it. The raw water pump mounted infront of the harmonic ballancer on studs off the block. The hub on the pump is 2 in diameter, made of cast aluminum. It had three triangular protrusions that interfaced with a mirror opposite piece mounted on the crank. The shaft it is mounted on is ¾, with an elliptical cotter key.<br /><br />Mine broke when a impeller failed and I cant seem to find another one. Could anyone offer any ideas where a replacement might be?<br />Thanks,<br />Kc5swi