I have a Johnson LT39 that we are preserving as found but would like to get it running. In the lower unit the driven gear is not connected to the propeller shaft is any way. Looks like it may have been a press fit that has given up. Can anyone comment on how this was originally fastened and if there is a fix. Don
The OP was asking about the prop shaft gear. I too have never seen a gear press fit to either a prop shaft or drive shaft. Look real close for a pin that may have been cleanly sheared off.
Tubs to the rescue again… I just found a parts list for the LT and was going to ask the OP to look for a hole in the face of the prop shaft gear. There is a spring shock absorber unit that connects the gear to the pump eccentric. In the parts list drawing it looks like a simple coil spring. Tubs first photo seems to be a enclosed unit, last photo the plain spring. Apparently, the OP has a part missing or broken.