Many ThanksShould be a tag with the engine serial number right around the engine starter area.
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If the tag near the starter is gone look through any literature that came with the boat. Both of my last two boats (bought used) had a folder from the boat manufacturer most of it was safety CYA stuff but in there was a mercruiser booklet that had the serial number for the power package. It looked like it was shipped with engine and drive to boat manufacturer.Where can we get answers