Santorin - shaft altenator


Good evening all,

I am trying to become educated on the shaft altenator on my 1990 Santorin. Any information you can provide would be greatly appreciated. Assuming this is connected as designed and it is not modified.

- start up operations
- maintenance / inspection
- time frame for operation
- do's and dont's
- any other relevant information

Thank you in advance.

SV Iris, SN027
Phuket (planning stages for departure to Abu Dhabi)

Ian Park

The alternator turns whether the engine is on or off unless you put the gear lever in reverse while sailing. Remember the warning 'Never put gear in forward' while sailing.
So, while sailing just remove key from ignition and put it ignition below. This turns power on from batteries to excite the alternator and start it charging. Before starting the engine again turn key to off, remove key, gently put gear into reverse to stop the shaft and alternator. Then into neutral and start the engine.
I think the diodes in the alternator are meant to prevent both alternators charging together, but Amel in Marin confirmed the above procedure for me.
I have done nothing in the way of maintenance other than visual inspection and checking belt condition and tension. Great asset - 13 days sailing Atlantic with batteries fully charged all the way.


Ocean Hobo SN96


Do not run the engine and  put the key in the shaft alternator "ignition" at the same time.  The separate keys should be on a welded loop.