Re: '82 4.5hp Seahorse--won't go into reverse
i think the problem is in Lower unit.
i'm carently working on this model.
under powerhead il shift mechanism, transmiting by shift rod to Lower unit.
if gears in shift mechanism are worn(but i doubt if they are) you wil not shift rewerse.
i think the problem is dowm.
there on you tube is a 2 movie how to disabe lower unit in Evinrude 8hp.its the same type of lower unit.
look for this movi first how to work with this