Re: 1979 35hp Johnson longshaft. Whats a fair price ?
if it really runs out nice, has good compression and looks good, not all beat up. I'd go maybe $250.00 with the intention of replacing the whole lower unit. Those motors are not that hard to find in our area and a nice working one is only worth about $500.00 if that. With the cost of the gear and the cost of having it replaced it's just much easier to find a donor motor.
On the other hand the 1981-1983 is a different story. The only lower units that will fit are between those years. I know because I have one that's been sitting in the garage for 3 years and still can't find a donor.