Re: What year is my 35HP Mercury?
Hi John, its always a good idea to start your own thread, rather than reply to another but here's the scoop:
Mercury built 2cyl 35hp motors from 1963 through 1989. Chances are that since yours is listed as 'Oil Injection' it is mid-to-late 80's. Oil injection for those motors would be mounted in the boat, and not known for reliability. I might recommend that you remove and discard the oil injection if not already done so. Premix the fuel manually 50:1, with a good TCW3 approved oil.
Mercury service manual is 90-42794--1 which covers 1984 through 1989 motors. USA s/n 6445653 & up (CAN 7209608 & up).
The serial number should be on a transom tag, or on a label on the tilt tube beneath the steering arm. If its not found there, look for a round silver welch plug on the motor, as quite often its stamped there. Should be 7 digits, and first one could be a letter 'A' or 'B' if its not numerical.
Good luck.