Re: Replace propeller shaft seal, 1989 50 hp Force
it is a standard BUNA o-ring. If the rubber is crystalizing in one seal then it is probably crystalizing in others. You should seriously consider replacing all seals. <br /><br />use your caliper to measure the inside diameter of the groove and the width of the groove. then order an as568a-xxx o-ring per those measurements. should cost you about $0.17ea<br />if cost is no object and you want only the best then order a quad ring (aka double sealing o-ring). I could run you as much as $1.50 each.<br /><br />while you are at it - use your caliper to measure the prop shaft diameter, cup diamter, and cup depth for your oil seal. then use a standard dual lip CR seal with SS spring and cup. It should cost you about $3.50.<br /><br />Alternatively, just go to Ebay and order an entire lower unit seal kit for $20-$30. You'll get standard o-rings instead of quads. However, I think the wisest course of action is to install new seal kit and impeller every spring. The cost of maintenance is always cheaper in the long run than the cost of repair.