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Harkers Island, NC 28531
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Riser Gasket, Blank for Mercruiser


  • Part #: OSC8503-GB

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Block off Riser Gasket used on Mercruiser V6 & V8 engines with center riser manifolds from 1983 & up. This is used when the manifolds are fresh water cooled. It fits Osco # 4354, Osco # 8503A & Barr # MC20-98502 risers
Replaces: Mercury Quicksilver # 27-863725-1; Barr # MC47-27-41811; GLM # 30220; Sierra # 18-0672; Mallory # 9-61422Genuine  Osco  Parts

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