Duetto 97 - possible water tank leak?

Hello all,
This might be a simple question, but when filling up our 97 duetto with water yesterday for the first time since we bought it, we noticed a reasonable amount of water coming from the front of the freshwater tank (near driver side front wheel). The water only started coming out once the tank was nearly full.
I have noticed in the manual that it mentions breathers in the tank and I wondered if it might be these causing this?
Any help would be great.
Thanks a lot
Jonny

The tanks have, as you said, breathers on the top. These are cleverly disguised as holes and the only way you know when the tank is full is when it overflows through these holes. Use some water and see if the 'leak' stops.

Great, thanks a lot Paul

Each breather hole should have a nylon plug in it. Shaped like a 'dumbell' a surge of water or full tank will close them but otherwise they drop down under gravity and allow the tank to breath.

In our Duetto the front ones were missing causing a leak through them every time I braked when the tank was more than half full.

The cure was to have AS drop the tank, seal all of those holes and run a breather tube back to the fresh water filler point.

Peter