Corrosion at the entry nipple to my holding tank

[panamajim]

I have corrosion on my Ezell 35 gallon holding tank at the nipple that exits the tank with 1 1/2 ID sanitation hose. Has anyone had this problem before.
My question is this. Is there a pipe that attaches on the inside of the tank to this exterior nipple to the bottom of the tank. I think so. I am thinking of repairing this with plastic and plastic Pvc pipe.. Any ideas Instead of using Aluminium and welding.. for a fast fix until I get to a welding place that does Aluminium .. Using 5200. to glue to the tank. I then must sink a pipe to the bottom of holding tank to extract effluent.

 

[Mike H.]

It sounds like the begining of the end for your holding tank. My aluminum tank corroded through in several spots and I replaced it with a poly tank. You'll have to replace it sooner or later.

 

[Peggie Hall HeadMistress]

You prob'ly have bigger problems than that

You're seeing first hand just how corrosive urine is...so corrosive that the average life of any metal--even 316 stainless--waste holding tank is only about 10 years...and the first leak is always only the FIRST leak. So the smart thing to do will be to replace the tank with a good quality plastic tank. Any repair should only be what's needed to last you long enough to get a new tank.

To answer your question...if the discharge fitting is on the top of the tank, yes...there is a pickup tube inside the tank. The emergency repair that I would make now is: cut out an inspection port size "plate" around the corroded fitting...replace it and the pickup tube with a piece of PVC or PP or PE and new piece of PVC pipe...screw them down, sealed with a rubber gasket...or if no rubber gasket material is available, any sealant.

Before you do any of the above, pump out and THOROUGHLY rinse out the tank...put lots of clean water--sea water is ok--into it via the deck pumpout fitting ('cuz that sends the water into the tank at the bottom to stir up any sludge so it can be pumped out...use the macerator if necessary...and keep adding water till what's being pulled out is only clean water. That'll not only make this job a lot more pleasant, but will also allow you see the condition of the bottom of the tank after you've cut the "plate" out of the top of it...and when you do, I don't think you'll question the need for a new tank.

Your best source for a tank is Ronco Plastics Ronco Plastics They make TOP quality thick-walled plastic tanks for a very reasonable price and have more than 400 shapes and sizes, including more than 100 non-rectangular...and they install fittings in the sizes and locations specified by the customer when they make the tank. They're in SoCal, so if you're headed home, shipping should be minimal.

 

[Arwen]

I just removed my Ezell aluminum tank from my 40.5 last week. Had a leak in the exact same spot you mentioned. What really caught my eye was all the imminenent corrosion spots on the bottom of the tank, where you cannot see. All of them were just held together by rust formation, ready to burst at any time.
I called Triple M, they are shipping my new tank this week, less than two weeks after I called.
All of the fittings I need I purchased at Home Depot, standard PVC.

Word to the wise,,,all of your buddies that swing by for an adult beverage on a regular basis will be nowhere to be found when you remove the tank!!

 

[Marco Garcia]

Roger,
if you can, before you install your new Triple M tank, can you fill it up with water and measure the volume. When I did mine last year I think it got full at 30-32 gls.
I do not think it makes any difference but is good to know.

 

[Arwen]

I should be able to, and will report back.

 

[BBC16385]

Yes, I had this same problem on the 35 gallon tank on a 1997 P 42 about five years ago.

I chose to go with another Ezell tank because they had the exact dimensions for my very tight space under the floor. I was afraid of a plastic tank not because they would not be able to build the right size tank but because the location of the 2 intakes, 1 air vent and 1 outtake fitting was so critical to the success of the replacement that I could not take the chance.

Ezell told me that they make the tank and fitting walls thicker now than they did in 1997 so it should last longer. Also, before we knew better, we put Clorox in the tank for odor control and I feel sure that contributed to the corrosion. Nothing goes in now except waste, salt water, toilet paper and Odorlos.

You must replace your tank. Repair is not an option. The hardest part is getting it out. It took hours. I had to set up a 4 to 1 pulley system and use a winch. A very hard job. The new tank will come out much easier so the next replacement, if ever, will be a snap.