Stray current in Volvo saildrive

[bigwow]

Craned out Bigwow today, the anode on the starboard prop was completely gone; the one on the leg was almost untouched. On taking off the prop there was also a lot of play in the hub to spline joint, new prop last year.
On putting the screwdriver to the anode securing screw I got a slight shock, I hadn’t switched the engine switches off at this point.
Where do I start looking? The engines 12 yrs ago, came all wired up all I did was connect the live and earth.

 

[changeman]

On my Volvo saildrive, the leg had to be completely insulated fron the engine. No bonding (earthing wire) whatsoever allowed.
Could be yours has been somehow bonded. This would cause extreme deterioration of anodes and more worryingly, possibly erode the walls of the leg.
Hope this is of help and also that I am wrong.