MSD's not just for dock pump outs

[c_witch]

Hiee all,

I've just purchased a new demetic 974 msd. It has a way smaller foot print then the old unit
that was in the head so I have decided then when I install it I will add a diverter and also set
it up for a seaside pump out as well. The holding tank on these is pretty small about 2 and half gallon or so which I'm thinking equates about 25 flushes.

While this might not be according to hoyle lol I think is shall work ok.
Outlet from msd into diverter. Outlet A diverter to deck pump out. Outlet B diverter to mercerator pump. Outlet from pump to bronze nipple fitted into bronze ballcock fitted
to bronze 90 fitted to bronze thruhull.
The highest lift on the whole pumpout circuit being about 14''.
And yes the msd does have a vent fitting and hose installed.

As of now I have pretty much spent the entire alloted budget for the refit. I think I'll end up over budget by around 300 or so .

Happy sailing,
Brina

 

[kenn]

I also have the small MSD with vent and deck pump-out, and I'm replacing the MSD with something newer, like the Dometic or a similar Thetford. Besides the pump-out, it's fairly easy (if not exactly thrilling) to remove and dump the waste tank directly... why wouldn't you just plan to do that instead of blowing extra $$$ on diverters and pumps etc?

Also, that extra plumbing would raise eyebrows if you ever get inspected. I would just keep the setup as simple as possible.

 

[dscribner]

Witch,

Does this flush with sea water or are you planning on pumping it into the sea? (Or lake,river, large pool). I think that's illegal in most, if not all, states. I once had to take the edge off my porta-potty though. We were about 9 nm out, it was full to bursting, and my son had food poisoning. He had eaten Dante's Shrimp with Annihilate Sauce the night before. Not a good time.

 

[c_witch]

I also have the small MSD with vent and deck pump-out, and I'm replacing the MSD with something newer, like the Dometic or a similar Thetford. Besides the pump-out, it's fairly easy (if not exactly thrilling) to remove and dump the waste tank directly... why wouldn't you just plan to do that instead of blowing extra $$$ on diverters and pumps etc?

Also, that extra plumbing would raise eyebrows if you ever get inspected. I would just keep the setup as simple as possible.

Hiee Ken,
Well I decided that I'd rather not have to undo the lines for the deck pump out and vent plus have to switch the fitting over in the tank itself to the one for manual disposal on shore. Plus having to do that while on the water is even LESS thrilling of an idea to me lol. I would have liked to have gotten the 975 instead of the 974 as it has twice the storage but we simply did not have the head room as even now it is a snug fit lol. In 3 to 5 years we hope to move up to a 35 footer and I figured I might as well get my feet wet now ie the mercerator pump and various valving etc. Also we do have some marina's here with dockside pump outs but not all and even then they still want to charge us the same as the big boys which is just robbery to my mind ie 2.5 gallon tank vs a 30 or 50 gallon.

Happy sailing,
Brina

 

[c_witch]

Witch,

Does this flush with sea water or are you planning on pumping it into the sea? (Or lake,river, large pool). I think that's illegal in most, if not all, states. I once had to take the edge off my porta-potty though. We were about 9 nm out, it was full to bursting, and my son had food poisoning. He had eaten Dante's Shrimp with Annihilate Sauce the night before. Not a good time.

Hiee DS,

We'll fill the flush tank originally with fresh water and may keep a 2 gallon jug of water on board for refill. On the other hand we may replenish with sea water while at sea with it. It will be rinsed with fresh water after every sail though. The diverter will allow for using a dock side pump out OR divert to the macerator pump and pump out at sea. The diverter is base mounted and can be locked with a padlock in either configuration. So normally it will be locked in the dockside pumpout. We won't be doing any freshwater sailing here so overboard pump out is not to much of an issue although there are regulations as to where one may pump out at sea here in Nova Scotia when within the territorial limits of the country.

Happy Sailing,
Brina

 

[Peggie Hall HeadMistress]

Nothing new or problematic about that installation

I've just purchased a new demetic 974 msd. It has a way smaller foot print then the old unit
that was in the head so I have decided then when I install it I will add a diverter and also set
it up for a seaside pump out as well. The holding tank on these is pretty small about 2 and half gallon or so which I'm thinking equates about 25 flushes.

A lot of people set up MSD portapotties to be pumped out or dumped at sea, and you've spec'd it out correctly, although I wouldn't spend extra money for bronze fittings where marelon or PVC will work just as well. Go with a Whale or Henderson y-valve...avoid Jabsco.

I've even known some that added a second holding tank...use the macerator to dump the portapotty into the second tank, then plumbed the tank for pumpout.

However, I'd swap out the Dometic 974 for a Thetford 365 MSD that holds 50-60 flushes.

As for "why not..." Brina... The whole idea behind MSD portapotties is to create a self-contained system that's simple to use, and requires none of the "hands on" that portable portapotties do.

 

[c_witch]

I've just purchased a new demetic 974 msd. It has a way smaller foot print then the old unit
that was in the head so I have decided then when I install it I will add a diverter and also set
it up for a seaside pump out as well. The holding tank on these is pretty small about 2 and half gallon or so which I'm thinking equates about 25 flushes.

A lot of people set up MSD portapotties to be pumped out or dumped at sea, and you've spec'd it out correctly, although I wouldn't spend extra money for bronze fittings where marelon or PVC will work just as well. Go with a Whale or Henderson y-valve...avoid Jabsco.

I've even known some that added a second holding tank...use the macerator to dump the portapotty into the second tank, then plumbed the tank for pumpout.

However, I'd swap out the Dometic 974 for a Thetford 365 MSD that holds 50-60 flushes.

As for "why not..." Brina... The whole idea behind MSD portapotties is to create a self-contained system that's simple to use, and requires none of the "hands on" that portable portapotties do.

How critical is it having to have the vent loop?? I plan on pumping this out thru the bottom which will be only slightly below the water line certainly less then 12 inches and maybe less then 6. Do I still need to add the vent loop?

Thanx,
Brina

 

[Peggie Hall HeadMistress]

Safety standards call for a vented loop in any line...

...connected to a below waterline thru-hull. It doesn't matter how far below the waterline the thru-hull is now...'cuz when water outside the boat starts filling up the boat, the waterline rises....and rises...and rises...till the whole boat is below waterline.