MS 400 Sump Pump

welippisch · 08-15-2020, 10:24 AM

Probably a stupid/basic question but learning the systems in a new to me 2007 MS 400. What actually drains into the sump that is located in the main stateroom? Does overflow in turn go into the forward bilge?

Thanks to all in advance.

**Bacchus** · 08-15-2020, 10:51 AM

On my '08 MS 34 T/HT the shower sump serves shower. Fwd AC and head sink. Take a look at the sump, count hoses and trace back as far as possible to figure out where they go or remove the top and observe while someone pours a cup or two of water in each. If a line goes fwd under bed it likely in the AC.
Should drain over board.

welippisch · 08-15-2020, 02:07 PM

Thank you for the quick reply. I'm going to cache that down today.

Jgutten · 08-16-2020, 06:52 AM

In the MS 400, the shower sump drains the AC condensate, the shower and the sink in the head. The galley sink drains overboard.

Clean it out every six months or so and check the switch and pump and you'll be fine.

welippisch · 08-16-2020, 07:14 PM

Thanks for all the previous information.

So looked inside the Sump Box. Full of water. The Rule 800 Bilge pump is intermittently inop, so I'm going to replace it. Connected to the outflow is a 3 inch long hose that seems to have a duck valve inside. I bought a Rule 800 pump with an attachment that's similar but no go on the connections. Does any one have a name /part # for the duck valve connection? Is that what it is?

Where does this all drain overboard?

Dougcole · 08-17-2020, 10:25 PM

The sump set up in the 400 is not a good one, it's not likely to ever work correctly. I had tons of issues with airlocks and overflows, which run into the FWD bilge but soak the plywood floor under the steps first, until I switched to a gulper pump. It's noisier but works way better.

My advice is to ditch the sump entirely. If you decide to switch and need help I can dig up the thread I posted on how to change it out.

mncruiser · 08-18-2020, 07:27 AM

I’d second the gulper pump recommendation.

In my last boat I had a similar sump setup. I tried to repair, no joy. I bought an entire sump/pump/switch setup new, and still had issues. The duckbill valve and the size of the pump was an issue, even with a 100% new setup.

The manufacturer of the sump box setup even knew there was a problem with the design, I called for support and they ended up sending me a bigger pump as I experienced airlocks often. I also had to remove the duckbill valve. If I remember the brand of the setup I’ll post it.

The setup did work well after the bigger pump, and it worked well for over 1.5 years at that. But it was a pain to get right.

I knew I had plans to sell the boat in the future, (I just sold it) but if I had longer term plans I was surely going to invest the time and effort to redesign using the gulper style system.

A search here on TF will probably yield results on the gulper.

Pmcsurf1 · 08-23-2020, 07:56 PM

Quote:

Originally Posted by Jgutten

In the MS 400, the shower sump drains the AC condensate, the shower and the sink in the head. The galley sink drains overboard.

Clean it out every six months or so and check the switch and pump and you'll be fine.

Our 2004 MS 400 is different. Sump pump is for shower and two ACs. Our head sink goes overboard.