Hi,<br /><br />Does a 1970's mercruiser 165HP 4.1L 6 cyl inline engine use leaded or unleaded fuel?<br /><br />Do I need to add an additive?<br /><br />Any help is appreciated thanks!!!<br /><br />Michel Brouwer.
depends on where in the 70's. in this country catalytic converters were mandatory in passenger cars in 1975. trucks were excempy. merc has a chart someplace about which engines must use leaded or unleaded with a lead subsitute additive.
I had a 76 model of that motor and it was right in the "transition" year. Had the valve train checked and it was okay for unleaded fuel---I think they started changing over in 75.
