Re: Johnson 1965 9.5 horse running issues help Home › Forum › Ask A Member › Johnson 1965 9.5 horse running issues help › Re: Johnson 1965 9.5 horse running issues help garry-in-michiganLifetime MemberReplies: 3583Topics: 31 August 4, 2017 at 7:37 pm #62594 Heat may have damaged the fuel pump diaphragm as well as the head gasket.. Be sure and check the prop shaft seal. They can be damaged by things wrapping aloud the prop shaft. You don’t want water getting into the gear case. . . 😕