I normally do not use a sealer on the cylinder head gasket but yours looks a little sketchy so I would use some on that one. The exhaust cover gasket should use a sealer. You should not use a sealer on the intake manifold and reed plate gaskets as you do not want to have any excess sealer gumming up the intake. BRP gasket sealer or Permatex Aviation sealer #3 are good choices.
Bob
1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1955 Johnson QD-16
1957 Evinrude Fastwin 18
1957 Evinrude 3022
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20
1982 Evinrude 25hp
“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."
