Well, you could use either the OMC type M or the OMC gel seal (along with Loctite/3M equivalents). The type M sealer is probably a little easier to use/less sensitive to prep that the gel seal, I just wish the type M came in smaller tubes for these small jobs. The gel seal works great but proper prep is necessary or it won’t work.
Needless to say, you must spend some time making sure all the old sealer has been removed and there are no high spots (especially around threaded holes) prior to reassembly as well. Old sealer/high spots on the block will cause the halves to be "shimmed" apart slightly when reassembled creating crankcase leaks and sloppy crankshaft fit.
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