Toilet Engineering

[Dockhead]

I have just spent a DELIGHTFUL afternoon disassembling and reassembling the Jabsco Electric Toilet Conversion in my guest heads in an attempt to solve a leak. The third time (plus 1/2) did the trick.

During the process I had a lot of time to think about how that miserable insult to engineering is designed.

Would it really be too much to ask, that someone would at last build a marine toilet that doesn't ruin every cruise with some stupid problem or another?

I need to blow off a little steam, so I'm going to catalogue the engineering defects which I observed in this device:

1. There are five -- count 'em, five -- sealed joints below the toilet's "waterline". Any flaw in any one of those and you have a heads compartment flooded with filthy water.

2. Two of those are sealed with paper gaskets which gradually just dissolve, inevitably leading to the aforementioned unpleasant and unsanitary event.

3. There is no way to take apart one of these without a flood of filthy water. Different eventualities during disassembly may even produce a geyser of filthy water. Oh, joy.

4. The lower impeller/macerater assembly is held to the motor by four long screws (for the amusement of the mechanic, they are of different lengths, so that reassembly is more fun). These screws go into either alu or plain black steel (not sure which) but in any case, after a few years they will corrode solid into the motor, so if you have one of these, Duralac the screws first thing.

5. The macerator blade, an exceptionally cheap piece of stamped sheet, with a flimsy tab to key it to the motor shaft, cannot be taken off without removing a nut which seems to have threads designed to jam to keep the nut from falling off (and to keep the mechanic from getting it off either). How do you hold the motor shaft while you're unscrewing it with the necessary (high) force? Oh, what fun. As it turns out, even destroying the impeller by jamming it with a screwdriver will not hold it tightly enough. So you have to disassemble the top part of the pump, with the supply impeller and so forth, remove the supply impeller, and hold the motor shaft from that end with vice grips. How amusing!

6. The motor housing is plain black steel which corrodes through the ordinary painting.

7. The heavy pump assembly is attached to the flimsy plastic toilet base with four screws which screw directly into plastic. This is a critical seal. If in attempting to achieve that critical seal, you slightly overtighten one of the screws, then you know what will happen. And don't ask how I know.

Really, these things cost hundreds of pounds. Would it be too much to ask that an actual engineer with a modicum of talent and skill would come up with some kind of non-idiotic design for these things?

My wish list for an ideal marine toilet:

1. Minimum of sealed joints. Best of all, any elements "below the waterline" of the toilet should be in a pan of some kind, to be withdrawn from the top.

2. A drain with plastic hose, which is capable of completely emptying the device for service without flooding the room with filthy water. Even my 20 year old washing machine has one of those.

3. All seals which can't be avoided altogether designed to just work, completely robust and foolproof. No fine alignment required like with the Jabsco joker valve flange.

4. All gaskets -- to the extent any are needed -- are made of durable, non-dissolving materials.

5. All screws go into metal, not plastic.


6. Powerful and robust motor in ball bearings, with stainless or really well corrosion-proofed housing.


7. The prototype of the device is taken apart and reassembled by a few different randomly chosen marine engineers. Difficulties are noted and the design is corrected to make it realliy easy to service, without problems like how do you hold the bloody motor shaft.




My other toilet is a Raritan Sea Era. It is even flimsier than the Jabsco, if one can imagine such a thing, and this flimsiness caused mine to self-destruct once when the macerator blade contacted the overly flexible pump housing. Oh, joy. It is also functionally worse in some ways, lacking any way to actuate only the evacuation pump in order to empty the bowl, for example, and with much lighter and cheaper motor and other parts. The motor is much less powerful, and is not up to any kind of heavy duty maceration jobs.

However, the Sea Era does have a few advantages over the Jabsco, including proper metal screw inserts, a better sealing flange for the joker valve, and only one seal -- the motor with macerator assembly is directly inserted into the toilet base. So I'm happy that at least I've never had a leak with it, unlike with those horrible Jabsco ones.

As I pulled apart my dedicated locker for plumbing and pump spares, I realized that I have FIVE spare toilets on board -- Jesus! Some usable others not, the unusable ones retained for cannibalization for spares. One Jabsco electric, two Jabsco manuals, and one Raritan. This is a reflection of how much trouble I have with these things, and how often I buy replacements. This is ridiculous. Will someone at last make a good marine toilet, which JUST WORKS?

[siamese]

My Thetford model 135 Porta Potti has none of those problems.

[pjShap]

There wouldn't be so many varieties if any one was perfect. Having said that, my Lavac toilet is pretty simple and very reliable. Pump is located above the toilet, not below. In 4 years I've rebuilt the pump once, and that was after the boat was on the hard for 4 years before I bought it.
https://blakesandtaylors.co.uk/lavac...ilets-41-c.asp
https://www.fisheriessupply.com/lava...-manual-toilet

[wingssail]

This is the biggest reason, along with noise and electric power usage that I have stuck with manual toilets and even my Raritan PEII is a frequent source of problems. I cannot imagine adding an electric toilet (or two) to my maintenance list.

Simple is better.

[Dockhead]

Originally Posted by wingssail

This is the biggest reason, along with noise and electric power usage that I have stuck with manual toilets and even my Raritan PEII is a frequent source of problems. I cannot imagine adding an electric toilet (or two) to my maintenance list.

Simple is better.

I have decades of experience with both manual and electric toilets, and in my experience electric toilets are far superior. They don't break more often than manual ones, are not really more complicated, and because of macerating are FAR less likely to clog.

I had a Raritan PEII in my last boat and prefer it to the Jabsco manual one, but it was not less trouble than any of my electric ones. It was so easy to clog that we followed the barbaric practice of bagging TP (shudder).

One advantage of the Jabsco manual toilet compared to the electric conversion, is that there are fewer joints, so fewer places they can leak.


One disadvantage of the Raritan PEII is that it leaks around the pump shaft. I used to keep a bunch of spares on board to deal with that. Had to change it more than once a year.

[Mike OReilly]

Composting head. Solves all your problems [emoji6]

[Windpilot]

8 years now with 2 vacuflush heads, most reliable heads I've ever had. Only maintenance has been duckbills and 1 cracked head base damaged by me. Easy no mess jobs, vacuum pump and tank only look complicated. Using freshwater to flush if you have it is better I think, plus it's much more user friendly for guests.
All my previous heads were messy, smelly and needed content attention.

[Dockhead]

Originally Posted by Mike OReilly

Composting head. Solves all your problems [emoji6]

Not on my boat!

[Dockhead]

Originally Posted by Windpilot

8 years now with 2 vacuflush heads, most reliable heads I've ever had. Only maintenance has been duckbills and 1 cracked head base damaged by me. Easy no mess jobs, vacuum pump and tank only look complicated. Using freshwater to flush if you have it is better I think, plus it's much more user friendly for guests.
All my previous heads were messy, smelly and needed content attention.

I've used Vacuflush toilets on friends' boats. We had more or less the same amount of trouble with them as other toilets. They may be inherently easier to fix however due to the admirably simple design. Just don't like the sealing lids and lack of maceration the latter is what apparently makes them more susceptible to clogging than other electric toilets.

[Windpilot]

Originally Posted by Dockhead

IJust don't like the sealing lids and lack of maceration the latter is what apparently makes them more susceptible to clogging than other electric toilets.

Just need to make sure there are no leftovers on the sealing lid, easily removed by lever action and flush and never a clogging issue using the right TP which is the culprit. The strong vacuum action easily tears that apart. After 40 years of marine toilets, over 8 years of vacuflush, that is what I noticed.
Non if this means a electric macerating toilet isn't good and will serve you very well. It's just my current preference.

[Phantom Jim]

I agree with Mike. In a Moody 54 you have two heads, no doubt. One could be a compost (not composting*) head. A lot of very sophisticated folk find them acceptable.

However, if is not your style, then you are going to have to exist with the existing engineering designs.

*Using the term compost head removes the impression that the head is actually composting to any meaningful degree.

[Anders]

Get a Lavac but get it with the manual pump not the electric pump.
I beleive I could pump a golf ball through my Lavac but have not tried to.

[goboatingnow]

Originally Posted by Dockhead

I have decades of experience with both manual and electric toilets, and in my experience electric toilets are far superior. They don't break more often than manual ones, are not really more complicated, and because of macerating are FAR less likely to clog.

I had a Raritan PEII in my last boat and prefer it to the Jabsco manual one, but it was not less trouble than any of my electric ones. It was so easy to clog that we followed the barbaric practice of bagging TP (shudder).

One advantage of the Jabsco manual toilet compared to the electric conversion, is that there are fewer joints, so fewer places they can leak.


One disadvantage of the Raritan PEII is that it leaks around the pump shaft. I used to keep a bunch of spares on board to deal with that. Had to change it more than once a year.

I agree ,my most reliable toilet was a simple Jabsco macerator toilet (Not the conversion ). Four screws to complete disassembly , didn’t leak

[valhalla360]

Originally Posted by Dockhead

Not on my boat!

He beat me to it.

People think nothing of dealing with raw liquid nasty sewage as they are bent over disassembling the toilet in a rolling boat.

But the idea of a simple composting toilet that is largely odorless with nothing to break or fail or fill up so you can't use...they are horrified.

[Phantom Jim]

"But the idea of a simple composting toilet that is largely odorless with nothing to break or fail or fill up so you can't use...they are horrified."

Nicely expressed. Different strokes for different folks. Pick the poison you want to deal with.