"Has to be a misprint - all th
"Has to be a misprint - all the 6E9's were definately 2 cylinder models.
In 1989 there were 8 distinct 40 horse Mariner models built by Yamaha.
The first 4 were "C" model twins (Manual Short, Manual Long, Electric Short, Electric Long) with serials all beginning - 6E9 then 009891, 314464, 106224 and 431768 and were copies of the 40FE/40FM/40FEML models respectively.
The next pair of 40's were Kerosene fueled (sold in the Asian market) - both rope start (short/long shaft models) with start serials 6F5 then 001483 or 306108 - these were based on Yami's own model 40GMK (which I have no other information on at all and have never seen one but since it was a "G" model it's safe to assume that it used the 4 cylinder commercial powerhead that became the Marathon/Magnum in later years in the gas versions).
The last pair were the 4 cylinder Marathon models based on Yamaha's model 40G - both rope start (short/long shaft versions) with start serials 6F6 then 018405 or 332945. Until the 1987 model year these had been marketed as the Mariner "Work" model (commercial).
Mercury parts doesn't even have listings for the Kerosene or Marathon (Yami built) models. Merc themself marketed both Marathon and Magnum models using their own 4 cylinder powerhead (which really confuses things if you are talking to a Merc dealer about a Yami model).
But at the end of it all, if the serial starts 6E9 it's a twin cylinder. Yamaha discontinued the "C" models in 1983 (in their decals/colours) so no further innovation or tooling for that model was done once it was discontinued.
They simply kept producing it for Merc until the line was completely scrapped in 1992. This ultimately means that regardless of what "model year" a "C" model Mariner is, it's actual year of production "technology wise" was 1983...."