Water at the foot of bed (main stateroom) – Mainship 390

/ shellerina

If you own a Mainship 390 and you are finding wet flooring at the foot of your bed, there are 4 possibilities to check.

1 & 2: Remove the mirror at the front-most bulkhead or “headboard” of your bed.

Behind mirror at head of main bed.

See more pics here:

https://shellerina.com/2021/06/25/at-her-berth-in-erie-pa/

There are two through-hull fittings that can be inspected / serviced there.

Starboard is the drain for your anchor locker, (shown above).

Port is the forward A/C unit’s seawater return.

If either of these plastic thru-hull fittings are cracked, which has been known to happen, then seawater will come in when you are underway. The problem won’t manifest itself “at rest” as the fittings are 12-18” above the waterline.

It is an easy and inexpensive fix.

3: A third source for water showing up at the foot of your bed is a clogged drain hose from the condensate tray under the forward A/C.

Newer A/C units have an FRP condensate tray under the unit (as shown above). Original equipment A/C units have this same tray and drain hose. Older trays are steel not FRP. The hose is a 5/8” drain hose that is typically plumbed to the shower sump box or simply just to the forward bilge.

If water spills out/over this condensate tray, in minutes it will find its way to the floor at the foot of your bed.

A clogged drain hose is distinctly possible after 20-25 years. Snake the clog from the lower end to prevent MORE water from coming out on your floor.

Clean the interior of the hose and unclog as best you can.

Once the drain hose is working, you have fixed the problem!

Removing the slide-in storage boxes under the foot of the bed will give you all the access you need.

I brought a charged garden hose down to surgically clean the condensate tray, and the aft bilge, pump, and shower sump.

While working on this, consider replacing the shower sump, or cleaning it if it has recently been replaced.

More pics of that sump system:

https://shellerina.com/2025/03/18/new-shower-sump/

Years ago, the cracked through-hull fitting caused this on our boat. It took weeks to figure out the source of the water! AND I know of others who had suffered the problem without knowing “Where is the water coming from?”

4. From Peter G: a leak in my forward wash down hose caused water at the foot of the bed too. Thank you Peter.

Addendum Feb 2026.

Unfortunately, Peter’d be correct.

After a freezing incident here in North Florida, we discovered #4 to be true. So, now we’ve been bit by 3 out of the four.

Fortunately: These are all DIY projects IMO.

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