75HP Merc, unknown year

[Diver_1]

I just bought a boat that has a 75hp merc on it and not sure of the year, I believe the serial# to be 6558940. I could only find what looked like a frost plug with this stamped on it.
Any help please? I am new to Mercs.
Thanks for any help

 

[Barnacle_Bill]

Re: 75HP Merc, unknown year

6558940 comes out to be a 1984, 4 cylinder.

 

[Diver_1]

Re: 75HP Merc, unknown year

Thanks very much for the quick reply!