Magic?

[s/v Dearbhail]

There have been several topics recently about engines with water intrusion and there is a discussion about water in the boat and bilge pumps. This has me seriously wondering how safe my own A4 is, specifically my cooling system. I'm wondering now why I haven't flooded out my A4 or sunk my boat yet.

There is not an anti-siphon loop/valve in my cooling system. Water comes in through the seacock, into a rubber hose, rises to the top of the engine compartment, the T-fitting for engine flushing and anti-freeze, then drops down to the water pump, through the engine cooling system and out the wet exhaust. The entire cooling system is below the water line except for those couple inches at the top of the engine compartment where the T-fitting is.

Are those couple inches the only thing that's kept the water out of my boat all these years?

[rigspelt]

1. You don't have any leaks in the cooling water system, so there is no reason why cooling water would leak into the boat.

2. If you have not have water backflow from the exhaust into the manifold and then cylinders, presumably your exhaust system is also secure. Perhaps you could describe the path and heights of the cooling water from the manifold through the exhaust.

[s/v Dearbhail]

I'll get some measurements and try for pics. There isn't a lot of room under the cock pit. The exhaust is much easier since most of it is readily visable.

I may not have any leaks today, but tomorrow, next week or next month could be different.

[sastanley]

Mark, Something interesting I noticed as I am ripping apart things in the Catalina...my 'anti-siphon valve' has a hose in the top of the loop where I would expect a valve to actually be located that runs to the sink drain. I guess it vents thru the sink, provided we aren't on STBD tack and heeling enough the sinks back up from being below the waterline..this was a common occurrence that I recall when I was younger.

Happy contorting!

[s/v Dearbhail]

Funny you mention the sink, been there and done that one. If I heel the boat over hard enough the water will come right in and fill the sink. I normally keep the hull valve shut but I was making some coffee underway, the boat took a couple good gust of wind, heeled over good and we had water in the people tank.

That anti-siphon valve shouldn't leak. That length of hose on your sounds like a way to route the water to the sink instead of dumping out into the boat.