autohelm st-50 knot meter

[edward cortese]

Have 36' 1995 Catalina mkll. When I pull knot meter transducer out of hull fitting and spin paddle manually, I get a reading at the helm pod. When I replace transducer in fitting and begin traveling through water, get no reading at helm pod. BTW, paddle is clean- no weeds, barnacles, gunk, etc; arrow on transducer is pointing dead ahead; and transducer is pushed through fitting as far as possible. Raytheon has no answer, and neither does General Electronics. Before I invest in specialist to tell me, no doubt, to replace it with new meter, any advice from you guys and gals with more experience and know-how than I? Thanks...

[capttb]

Is it possible that paddlewheel is in backwards? With arrow pointing forward, flat side of "cup" on paddle should also face forward at the bottom.