Re: Year and RPM range for my motor 70HP Force ?
That was an odd time for serial numbers and models of Force motors.
It was just after the purchase by Mercury, with some motors using the old system, some the new.
Best I can narrow it down to is 1991-1993.
Betting late 1991 or early 1992.
OE000001 - OE065371 1991-1993
Lots of different parts were used during that 3 year period, carbs, spacer plates, tnt units, several different ignitions, fuel pumps, etc.
The most common parts, that were different, were the fuel pumps - square Merc type vs oval 2 stage chrysler type; and the ignitions. Blue coil prestolite ignition - vs Merc early switchbox - vs Merc newer switchbox.
Sometimes you can find a date on the starter, or a white paper production line label on the water jacker, flywheel, or ignition board. It may contain a date, model number, or serial number.
Or, you can post photos of the fuel pump and ignition board, and we can try to narrow it down for you.
Rpm, 4250-5250 or 5500? Mine was set up to run 5600 with an empty boat.
