Originally Posted by O C Diver
Is your syphon break on the suction or pressure side of the pump?
The hose from the heat exchanger, goes up to a U pipe with a Scot Vacuum breaker valve (with a little spring) and then down to the exhaust elbow. The anti-siphon value is about 13" above the top of the elbow. The anti-siphon value is about 7" about the waterline.
What I don't like about the Scot vacuum breaker is that when salt or anything gets in the valve, it sprays saltwater in the roof of the engine room.
I have considered taking the breaker off, and running a 3/8" tube across the ceiling (5 feet) , into the aft wall and up a few feet to a vent screen. My concern with putting a tube/hose horizontal is that it could sag and create a water/airlock.