Gurgling noise in the anti syphon valve

[estekey]

My anti syphon valve is connected to the cockpit drain on a center cockpit Hallberg Rassy

When the engine is in idle, especially when starting or after a prolonged trip, I can hear loud gurgling noise from the cockpit drain. It has developed over that last few weeks, I have not noticed it before.

Is that normal?

 

[VicS]

My anti syphon valve is connected to the cockpit drain on a center cockpit Hallberg Rassy

When the engine is in idle, especially when starting or after a prolonged trip, I can hear loud gurgling noise from the cockpit drain. It has developed over that last few weeks, I have not noticed it before.

Is that normal?

Broadly speaking two types of antisyphon device.

One with a little valve on the top that opens to admit air to break the syphon when you stop the engine. This type needs regular checking to ensure that is is operational and does not become clogged

The other with no valve but a small diameter tube from which water will "pee" while the engine is running.
It can either pee overboard or into s cockpit darin where it can be seen. All the while it pees OK you know its clear and will break the vacuum when the en gine stops.

I guess you can hear water being discharged from the latter type. Worry and investigate if/when you cannot. Better relocate it so that you can see the pee stream.

Both types are illustrated in the Vetus catalogue

Usually a restrictor in the discharge to limit the flow. Check yours has not lost the restrictor and is now running "full bore"

 

[VicS]

 

[estekey]

Thank you very much.
Very clear and educational.
Best regards, SK