vetus vent on cooling inlet..... why?

[smeaks]

On my volvo 2002 the raw water from the pump is delivered to the engine via a brown "vetus" device mounted well above the engine. the device has an inlet and outlet to and from the engine and a small diameter spigot from the top. What is the purpose of this device?

thanks for any answers

 

[Phoenix of Hamble]

Raw water from the pump or raw water to the pump?

If the latter, then its an antisyphon valve to stop water flooding the engine...

 

[smeaks]

pump-vetus-engine.... I think.. reason for asking is I think the spigot is seeping sw into the bilge... possible culprit .... foam is wet around it and a couple of drops visible.

 

[westhinder]

Indeed an anti-syphon valve, it sounds to me. Creates an air-break in the circuit to prevent raw water from syphoning up the circuit, filling the exhaust pot and overflowing into the engine. Had one fitted after exactly that happened. Ever since, we have had a small tell tale jet from the side of the boat when the engine is running; very helpful to check that there is actually water supplied to the engine.

 

[jfkal]

There should be a hose attached to the spigot which leads overboard in case the valve salts up. Dismantling it and cleaning my be a temporary solution.

 

[jfkal]

BTW the sequence should be:

Inlet, strainer, pump, engine, vetus, mixing elbow. At least thats how it is on my Yanmar /forums/images/graemlins/ooo.gif

 

[boatmike]

Not necessarily. It works the same either side of the heat exchanger manifold. It lets air in at the highest point of the cooling system when water pressure reduces to allor water to run back down the inlet and exhaust.

 

[Endeavourquay]

Its an anti syphon device, when the water pressure in the pipe drops because your engine is no longer taking the water for cooling, the spigot opens and lets air in and any water that still wants to come through will either be taken away in a thin tube or spat out to your bilge. It stops the cooling water 'syphoning' itself into your engine, (as happened to me in January /forums/images/graemlins/grin.gif)

 

[smeaks]

thanks everyone mystery thing solved!