Problem fixed: Wanted to change the length of the lower unit from 25 inch to 20 inch to fit a different boat.

Basically had to completely strip the lower unit and fit a 20 inch drive shaft and a different water tube and modify the length of the clutch shaft. Then had to clean and reassemble with new seals, o rings gaskets etc. There was also a crack in the casing where the propeller shaft assembly enters the housing. This seems to be a common occurrence with this model. Welding up the crank is not a satisfactory remedy as the crack will soon reappear beside the weld. What I am trying, is to drill about 3 holes along the crack line and then filling the crack and the holes with Devcon both inside and outside the housing. On refitting the prop shaft assembly to the housing I have covered the surface between the housing and the prop assembly with Sikoflex to prevent water from entering this space so hopefully preventing corrosion from occurring here as this was the cause of the original crack. This crack only impacts the area where the exhaust exits and doesn't compromise the area which houses the gearbox.