X#!&XX!! Watertank Lids

[jpendoley]

My water tanks are filthy and the "inspection ports" are just about impossible to open. I have to tap the lids out with a mallet and wooden drift every time I want to open them. They are 6" Beckson plastic ports that leak like sieves if I fill the tanks to the top. Has anyone else successfully installed inspection/cleaning ports? I thought the lids were jamming because the rings were twisted, but they jam even when the rings are removed from the tanks.  I lose tank capacity because I can only fill them three quarters full as they leak when heeling. Very frustrating!

[SVJourney]

I had the same ports.  They leaked bad and they were only 4" ports.  Someone on here managed to get new Beckson ports to seal up by building up the fiberglass around the port so it couldn't flex, then sanding the openings completely smooth and flat before mounting the port bases. 

If I were going to fix it forever I would install rivnuts or nutplates and bolt a flat plate down with a gasket.

[Jordan]

I've got the same issue. I think it was sea dragon that cut the tops off and installed 50 gallon flexible ones.

[jpendoley]

Am going with rivnuts and 3/16 aluminum tops-gasket and refair the top to make a good base to attach to.  In for a penny in for a pound.
Good suggestion on flexible tanks, but my experience says they will chafe and fail eventually. The fibreglass tanks are hefty and generally maintenace free except for the lids.  The beckson lids offer nothing but headaches.

[Jordan]

Plumbing – I completely redid the plumbing on the boat. I started by cutting out the forward 50 gallon water tank for conversion to storage. I cut the tops off both 50 gallon settee tanks, lined them with high density foam flooring I found at Lowes, and placed flex tanks from Plastimo inside each. My main freshwater pump is a Shurflo 3.3 GPM Aquaking. For my deck washdown I chose the flush mounted deck fitting originally produced by New Found Metals, now distributed by Jabsco. This is fed by a Shurflo Blaster pump with a diverter valve to choose either fresh or saltwater rinse. The deck fitting I installed along the side deck to allow easy reach to both the foredeck and the cockpit. All interior faucets were replaced with Price Pfister fittings. The cockpit shower is a SSI Plastics Ultimate Cockpit Stowaway shower. This shower required the smallest cutout we could find.

**update 7/06** I can't ever get the Blaster/flush mount plug to prime the pump. I think it always get airlocked. Will have to examine this installation...maybe that's the problem. To this day, we haven't touched the cockpit shower.

**update 4/09** I figured out I could prime the Blaster by blowing down the hose after I plug it in.  Nice.  Never once used the cockpit shower.  No major problems with the water system.

Here is the report card over a few years for that change, plus a part I missed about the foam.

And it wasn't sea dragon, it was GetLostOnPurpose.

Source

[SVJourney]

Am going with rivnuts and 3/16 aluminum tops-gasket and refair the top to make a good base to attach to.  In for a penny in for a pound.

Riv nuts into aluminum backing plates inside tank?  Say 2 half rounds maybe.  Although you could dome nut plate directly into the fiberglass and seal from below.  #8 or #10 screws.

[jpendoley]

I think rivnuts is not the right description. I am envisoning putting aluminum lids over the openings and using threaded inserts (sleeves?) embedded on the underside of the tank tops. That way I can bolt them down with machine screws.  Called them rivnuts, but threaded inserts is probably a better description. 
Tomorrow I go to the town dock to scrub those tanks spotless so the admiral will deign to drink water from the tanks.  I never noticed a problem when I was a bachelor....

[SVJourney]

Lol, for the admiral its all about filtering,  Big assed activated charcoal filters.  Even fiberglass tank water with chlorine is good then.

[P69]

Jim,

To get a perfectly even mating surface, mix up epoxy into a putty, spread it around the opening, the place a perfectly flat piece of something (that won't stick to epoxy) on the putty and squish it down a bit. Wait for epoxy to cure.  When you remove the perfectly flat piece of something, you will have a perfectly flat mating surface. Grind up the edges and install the threaded inserts. If you need to thicken up the tank's top to give the threaded inset enough penetration, lay up some 1708 with  epoxy, then  use the epoxy trick to get a perfectly flat mating surface. 

The threaded insert will unlikely hold well in the existing 1/4" or 3/8" top thickness because polyester/cloth/mat doesn't do well as a tapped medium.  You should consider laying up layers of 1708/epoxy to about 3/8", rolling each layer down with a fin roller to get good density, then the threaded inserts will  likely keep a good hold.

[jpendoley]

I have been looking at your tank work and gleaned quite a bit from your description of your process. My boat has come back together in large part because of the projects you have shared. Very inspiring thank you! This forum is a godsend for an English major and boatwright wannabe.

[P69]

You're welcome. I'm glad the information is useful.

I might have misinterpreted your plan incorrectly:  that you will install threaded inserts, penetrating the tank top. This will cause potential leak at each insert.

Instead, forgo threaded inserts. Just laminate 3/8" to 1/2" perimeter around the access hole (17oz biax, no mat or 1708 with epoxy), then tap into that from the top without penetrating the tank. epoxy/biax taps well and holds machine screws well. 

Depending on screw size, you might only need  1/4" to 3/8" thick  built-up perimeter around each hole. Rule-of-thumb for substrate thickness is thickness = dia of machine screw, but you have to add about 3/16 for the pointy end of  the tap, unless you use blind taps, but then you still need an small allowance for crap that falls to the bottom of each tapped hole.  I've used this method many times (laminated epoxy blocks, tapped for machine screws)  and use 3/8" thickness for 1/4" machine screws and 1/2" for 5/16" machine screws.  For 10x24, you can probably get away with a thick 1/4" for the tapped substrate.

Again, laminate the desired thickness, apply epoxy putty and press a flat piece on top to get perfectly flat mating surface, then tap for the gasketed ring.

[jpendoley]

Awesome advice-thank you. Scrubbing the tanks at the moment, rinsing and draining over and over. The admiral is on a mission!

[jpendoley]

The tanks are spotless-well, almost spotless, We scrubbed them all out, bleached and flushed several times. We installed an undersink drinking water filter on the whale foot pump driven outlet just for drinking.  Pressure shower and faucets not filtered beyond the screen on our 12v pump. The foot pump would not work with the filter cartridge which filtered for essentially everything until we stepped down to a less rigorous filter which only filters for sediment and flavor. Water tastes good now, but the foot pump flow is slooowww.

Regarding the water tank lids that don't seal: am thinking of enlarging the openings to 10" squares for easier access and covering with 1/4" 12x12 clear acrylic.  I will build up the tank mating surfaces to flat with the suggestions made by P69 and make gaskets. Thinking with clear acrylic, I can check water level by eye and only remove the lids at season start and finish for maintenance. Anyone see a problem with using acrylic? All input much appreciated.
Jim

[Jordan]

Do you have any pics of the process? Or the clean tanks? We can't even reach everywhere in our tanks, so we haven't bothered scrubbing them yet.

[SVJourney]

JP, Only problematic part to acrylic I can see is cracking.  Read up on drilling acrylic if you haven't done it before as the holes are where the cracks will propagate from. Rounds will be less likely to crack than squares, but either should be fine.  I like the idea of being able to check tank levels that way.

Jordan, most people have no access to their tanks for cleaning.  Chlorine shock and flush every once in awhile is your best bet along with filtering for safe water if no access.  We always added 1/4 cup of bleach to each tank when taking on water while cruising.  Even stateside water can have organisms that your body isn't used to.  The activated charcoal filter takes out the chlorine along with the taste from the fiberglass tanks that some people complain about.
https://www.homedepot.com/p/GE-Whole-House-Water-Filtration-System-GXWH20S/202073874
Replace cartridge with $5 charcoal filter from the same place.  Just one easy budget solution.  There are tons of others out there.