I just completed a fuel pump conversion on my FD-12 and used the Sierra 18-7350 pump. As Frank noted, you need the intake bypass cover from a 1960 or later motor, OMC part number 307477. Some folks have also fabricated an aluminum adapter plate to use with the fuel pump in lieu of the factory bypass cover.
Bob
1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1955 Johnson QD-16
1957 Evinrude Fastwin 18
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20
“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."
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