Re: LU compatibility 85 Johnson 8HP
I'm pretty sure most of the 4 (Deluxe), 4.5, 5, 6, 7.5 and 8 hp models of the 1980s all used the same lower unit. The 4 & 4.5 models used a smaller grommet in the waterpump for a smaller diameter water tube, but were otherwise the same unit. There may have been some subtle internal changes in the range, but as a unit they should swap around... Might even stretch into the 1990s, but no earlier than 1980. For instance, a 1979 6hp lower unit will NOT work...
