Just as a WILD GUESS it could be that your gearbox and shaft are producing
electrical noise when they start to rotate.

Broken earth wire somewhere?????

regards

David

On 5 June 2010 10:23, banjaro2002 <willem.j.kroes@...> wrote:

Sonic speed gives a lot of surprises on my Amel Santorin. Every time the
boat was launched readings are different. So I had to adjust the spacing
knob in instument black box.
But now I experienced a very strange 'behaviour'of the instrument. When
motoring there is no reliable reading (light is out). When engine is
stopped, fine accurate readings and of course the light comes on.

When starting the engine (not in gear) the light stays on, but goes out
when putting the gear on.

Is there anybody who can give me a clue were to look?

Willem J. Kroes

Amel Santorin # 69 "Kavanga"

[Non-text portions of this message have been removed]