Looking for low profile fittings for a new holding tank

[plenny7]

I have a '92 Hunter 33.5 with the original 20 gallon aluminum holding tank. It's way past time to replace it and I'm planning to do just that this fall, hopefully before it leaks.

It seems to be a pretty simple project and I was happy to find a 20 gallon Ronco tank which fit the space perfectly. Or so I thought.

Ronco supplied some fittings and when I saw them, I knew immediately what I had neglected to take into account. The height of the fittings. The original aluminum tank has welded aluminum fittings which make sharp 90° turns. The fittings supplied by Ronco stand tall and proud and will not work.

I could get a 15 gallon tank with the same footprint which would work with the fittings supplied by Ronco, but first I'd like to see if there's a low profile 90° PVC fitting available. I only have 2.5" to work with on the tank I've already bought, but by getting a new tank with different fitting locations I could get just a hair over 3". I'll be using 1.5" Raritan Saniflex hose.

Any ideas? Or am I destined to go with a 15 gallon tank?
Are there better options for fittings?

Here's the new tank fittings, and the include dip tube, as well as a shot of the original fitting.

 

[Peggie Hall HeadMistress]

It took some searching but a google search turn up several sources that MAY have what you're looking for.

--Peggie

 

[plenny7]

Thanks, @Peggie Hall HeadMistress , I did some google searches and anything I found that had dimensions was too big. I knew it was a long shot but I thought perhaps a fellow boat owner may have come across a solution. Part of the challenge is that the elbow needs to face a particular direction when installed so a simple threaded fitting may or may not work, depending on the orientation when tightened.

If I go ahead and get the shorter 15 gallon tank, do you think these are the proper fittings? I'd have to cut the dip tube down of course. They only provided the diptube fitting so I still need to get the fittings for the vent and the input hose.

Before I get too far into this again I need to go back and re-read the portion of your book which discusses this.

 

[Peggie Hall HeadMistress]

You can tighten the fittings hand tight plus enough to aim an elbow where it needs to go. Wrapping the threads in plenty of Teflon tape should prevent 'em from leaking.
15 gallons is awfully small for your no discharge waters unless you can learn to be very frugal with flush water. What's the make/model/age of your toilet?

 

[plenny7]

We have a Jabsco manual toilet. I'm not sure if there's a model number associated with it, nor do I know the age. I don't think it's original. A photo is below. I'm not a fan. I replaced the pump 2 years ago. It worked great for two years but this year it won't draw lake water for the flush. I should buy two pumps next time...one to install and one to keep as a spare.

I'd hate to decrease the holding tank capacity if I can avoid it, but we are just day sailors and have easy access to the pump out dock, and we can all use the marina bathroom before heading out for the day. For 4 days of sailing with an average of 5 on board per day, and using gallons jugs of water for flushing (so we could at least measure the volume of flush water), we estimate we put less than 5 gallons in the tank.

 

[Peggie Hall HeadMistress]

Love the tape across the seat!

And there's always the lee rail or the transom if necessary and you have the privacy. You shouldn't have to bring 5 gal jugs of water aboard to control the amount of flush water...just learn to use the "dry" mode to do more than just push the last of the flush "out the door." But before giving up on the larger tank...maybe we can find another location for it that has enough clearance for "standard" size fittings?

Before buying another pump assembly for the Jabsco, you might want to consider spending just a bit more and upgrading to a toilet that'll last 20 years if you just keep it lubricated and put a rebuild kit in it every 5-6 years Raritan PH SuperFlush It's available as either a complete toilet or a "conversion" (everything south of the bowl, which means you get to keep the bowl seat and lid from you Jabsco) and the mounting bolt pattern matches your Jabsco. And the handle telescopes so it shouldn't be in the way of anything. Get a quote from Dave in the sbo.com store.

--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein

 

[plenny7]

@Peggie Hall HeadMistress , Ironically your question about our head got me thinking about replacing the entire unit rather than replacing the pump every year or two, and a half hour of researching on the web lead to to the exact model you're suggesting. Of course it's no surprise that much of what I was reading was your posts recommending it. I'll definitely be getting that Raritan PH SuperFlush. From what I read, it should be an easy replacement of the Jabsco, is that right?

We'll be back on board this weekend and I'm going to take a better look at the space around the tank, take more measurements, and determine my maximum dimensions. It's currently under the starboard settee, very close to the head and I'd really like to keep it there.

Further searching on the web has led me to some discussion by you and others about using Uniseal fittings. With Uniseal fittings, a 1.5" flanged fitting, and a 1.5" tight elbow, I think the entire assembly would be less than 3" above the tank. I'm not sure how the Uniseal would work with a dip tube, but I found this Trionics Pump Out Kit which appears to do just that.

The jugs were temporary because we were without a water tank that weekend (leaking tank, rotted bulkheads...a mess that's now taken care of). It just happened to also make it easy to estimate how much we were filling the tank for the weekend. Now we're back to using a red solo cup and getting water from the faucet.

 

[Peggie Hall HeadMistress]

I don't think you'd gain anything with the pumpout kit 'cuz you'd still have to put a hose fitting on it. Let's brainstorm all this on the phone...If you'll send me a PM I'll reply with my phone number.
--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein

 

[Allan12210]

Plenny,

I encountered a similar situation last year as well. There was only 2-1/2 inches between the tank surface and the underside of my settee. I ordered the Ronco tank without fittings and used the Uniseal for the tank penetration. Then I located barbed 1-1/2 inch PVC elbows that glued to either the dip tube or the delivery tube to be inserted into the tank (LASCO 127957 from Walmart). Prior to gluing, I cut off some of the PVC leaving only abut 1/2 inch to glue. That was plenty. Total profile height was 1/4" higher than the outer diamater of the sanitation hose. It fit with about 3/4 inch to spare. Here are the links:

https://www.amazon.com/gp/product/B071JWJ2J6/ref=oh_aui_detailpage_o02_s01?ie=UTF8&psc=1

https://www.walmart.com/ip/LASCO-Elbow-90-Insert-x-Slip-1-1-2-In-PVC-127957/181196663

If you try to glue the PVC fitting to black ABS pipe, use the Green glue available at Home Depot. Regular ABS or PVC cements won't work.

Hope this helps.

Allan

 

[plenny7]

@Peggie Hall HeadMistress I just sent a PM.

Thanks, @Allan12210 that seems very similar to my predicament. I believe I need to use smooth fittings rather than barbed though. What did you use for the dip tube and delivery tube?

Perhaps I might be able to salvage this Ronco tank if I can plug the holes in it now and drill new holes in it for the Uniseals.

In researching this project, everything I've seen recommends going with double hose clamps on every fitting. I see you just have one.

 

[Allan12210]

@Peggie Hall HeadMistress I just sent a PM.

Thanks, @Allan12210 that seems very similar to my predicament. I believe I need to use smooth fittings rather than barbed though. What did you use for the dip tube and delivery tube?

Perhaps I might be able to salvage this Ronco tank if I can plug the holes in it now and drill new holes in it for the Uniseals.

In researching this project, everything I've seen recommends going with double hose clamps on every fitting. I see you just have one.

I am not aware of smooth fittings, but if you can insure they won't slide off or leak, I guess that works. Since I worked this project backwards, I bought a length of black ABS sewer pipe first, then found no suitable fittings with a low profile. After searching, I found the PVC elbows and not wanting to toss the ABS (cheap and lazy), ended up using it instead of just buying a piece of 1-1/2 inch white PVC pipe, I got the proper glue from my neighbor. If you make your own dip tube, cut the bottom at a 20 degree angle so you won't leave a lot of liquid/solid in the tank when it breaks vacuum. I got that tip from Peggy.

Plugging those existing holes shouldn't be an issue. Drilling the new ones was easy in polyethylene and the Uniseals fit really tight when the pipe is inserted. No way for leaks or odor escape. I used one of those cheap hole saws that come with about 7 different blades on a common arbor. Note on my vent I used a 1" pipe (and appropriate Uniseal) for lots of ventilation. You'll find on line the hole saw dimensions for the 1" ad 1-1/2' Uniseals. Use hand soap to insert the pipes. The nice thing is you can aim them any way you want.

I just make the single clamp twice as tight. Just kidding. I would have used two but at the time I ran out and didn't go back to the store. My holding tank is stand alone and well above the water line with one inlet from the head and one outlet to the deck fitting (dip tube). I can not discharge it overboard, so there is little risk of seawater coming in if a hose came off. But, I will put a second clamp on like I have on the hoses that are connected to the overboard discharge. In my case I have both the isolated holding tank and an Electro Scan system for direct treated waste discharge where allowed. I use a diverter valve to switch head output between systems. Those are all double clamped. Unfortunately more and more areas here are prohibiting discharge of treated waste, so I may be forced to retire it permanently.

Allan