[MC1600]

This ones become a real head scratcher for me…

When underway for cruises of like 1+ hours, the aft bilge will occasionally come on. Like every 10-15 mins. I’ve never noticed it coming on automatically when we’re at the dock, but if I flip the switch at the helm, there’s usually a bit of water in there (10-15secs or so). 

So I started checking. First I found a stream of oily water coming from the genset. Discovered my water pump was weeping, so I replaced that. Still happening. No water is accumulating in either engine bay. Bone dry. Both backing plates for the struts seem dry and secure. 

My next point to check is going to be the rudder posts. But as I’m looking, is there anything else about this model I should be looking at? Anything wonky that could be letting water in? We spend a lot of time on the boat not underway, and I’ve never noticed the aft bilge triggering when not underway, so it’s got to be something that’s forcing water aft when we’re on plane. 

Only other thing I can think of is condensation from the ac units, but they go into sump boxes, don’t they?

[jclark003]

Had unexplained water entering aft bilge spaces on a 52 sovran/express. Turned out to be coming in through a dinghy davit socket in the swim platform. Was hard to find. Another member had a similar problem as well. I am not very familiar with the 40 express but if it anything like the 52, the platform is open to the aft bilge spaces. May be worth putting a camera back there or look to see if there are any telltales of water getting in there. The platform probably has a seam under the rub-rail that is vulnerable to piling strikes.