It would seem that the use of araldite on the propeller and u-joint doesn’t give you many options. The suggestion of using some form of sealant on the wood in and around the area where water seeps in is a good one, but water will find its way into anywhere.
It’s a real shame and it looks a good boat from the pictures provided.
The only suggestion I could make would be
- undo the grub screw at the motor end (if not glued) of the u joint
- undo the screws holding the motor to the engine mount and remove the motor
- the brass collar and red plastic part of the u joint could now be removed leaving just the brass collar attached to the prop shaft
- put a spanner or grips on the brass collar and put some protection over the propellor and put mole grips or something similar over it. Then carefully try the break the glue hold by twisting the brass collar clockwise and the prop end anti clockwise then the opposite - small turns at a time
- a couple of things could happen here either the prop will come loose - bonus as now more surface to grip direct onto shaft. Or the shaft will turn inside the brass collar and can then be set up to reduce the clearance issue have at prop end - even better
- the down side could be the outer shaft tube could rotate and break the glue seal that goes through the hull 🙄
- if the shaft moves and comes away from the brass collar just buy a new u joint from e bay
- hopefully the shaft and propellor have survived and can be reused. If not then more spending or I may have a spare shaft that may fit and would happily send it you
- then it’s just setting up the propellor clearance to the outer shaft tube to achieve a minimum clearance of 5thou and this will then stop water ingress
It may sound daunting but I removed my entire outer shaft tube and refitted it with the help and guidance of people on this forum. I like you don’t have a clue but these guys give you the confidence to give it a go 👍
Also you’ve given me the bug to restart my 10 year ongoing project 😆