I have a 75hp 3 cly motor from 78. Last summer i was ridin down the local river and i think i hit a stump under the wateri was goin a slow speed when the motor bumps and quites goin foward although it will still go in reverse. When i got the boat home and drained the lower unit oil i noticed it had a burnt smell to it. I have the lower unit off right now but cant get the shaft that runs to the motor to come out to check the gears. Is there something that is holdin it in and is it really worth fixin or should i just try to fiind another lower unit. If so do i have to stick with one from the same engine or are other units fromdifferent hp able to be used? And where can i find a lower unit in north or south carolina?