If the point where the cooling water is injected into the exhaust is less than 15cms above the waterline, then when the engine is stopped, there is a risk that cooling water will siphon into the engine.
This can be prevented by fitting a Vetus air vent at least 40cm above th waterline. Anti-syphon device ASD38H has 4m of hose and a skinfitting and is suitable for hose 38mm.
Airvent ASD38H comes complete with a skin fitting, hose clamps and 4 metres of breather hose. It is also suitable for use with under-waterline toilets and/or the discharge pipe of a waste water tank. Can be easily dismantled by hand for cleaning.