Holding tank leakage common problem?

[Ozz]

I have read many accounts of leaking tanks, usually as I recall it is the galley, or kitchen tank that is the culprit, but not always so.
Our kitchen tank started leaking a few month's ago. I forgot to drain it and the water backed up into the sink. I usually try and drain at 3/4 full, easier on the tanks. I closed the drain valve and in the next cycle, it leaked all over the place.
I have had to leave the valve open since when camped.
It is good to fill the tank, then drain. The reason is that if you open the drain and leave it open, there will be a scum and debris line inside the tank, and build-up in the drain line of that tank. A rule in drainage is 1/4" per foot. This is because the liquid and solids are a mix with the 1/4" per foot, too steep and the liquid outruns the solids. If you check all the lines are at this incline, RV's and stick homes alike.
I just checked the tank yesterday, I had an access hole in the black bottom plastic, as I installed an aftermarket tank monitor, the sensors are on the tank. I saw the leak when I opened the cover. The scum line on the outside-bottom of the tank pointed it out clearly.
The leak was on the drain area, where the tank was formed for the drain, they must stretch the plastic to make the bulge where the drain is attached. My leak is only about 3" long at the very bottom. I will take pictures of the leak and the repairs.
I did some research on leak repair. It seems welding the plastic is first choice, but that is a learned skill and takes equipment. The black plastic material is extremely difficult to patch, it's slick.
Fusing the plastic is the key, you should drill a hole at each end to stop the crack from progressing.
I have ordered a kit from Amazon that fixes these tank leaks, it melts the plastic and fuses it solid.
"Plasti-Mend ABS Plastic Repair Kit for Holding Tank Repair"
Misc.; $36.50
http://www.amazon.com/Plasti-Mend-Plastic-Repair-Holding-Tank/dp/B003JC3UB2
I'll take pictures of the process, should have the kit and a few days.

[Tom S.]

If I ever have to remove the underpan on our trailer for any reason, one thing I will look into doing is reinforcing the tank supports - if there are any!

I hope I haven't just jinxed myself!

[DQDick]

Once again, thanks Ozz for keeping us informed. Looking forward to the final fix.

[SlickWillie]

quote:Originally posted by Tom S.

If I ever have to remove the underpan on our trailer for any reason, one thing I will look into doing is reinforcing the tank supports - if there are any!

I hope I haven't just jinxed myself!

As far as I know, the tanks are supported only by the lip, a no-no according to Travel Star.

BTW OZZ, someone on here patched a tank with 3M 5200 marine adhesive and sealant. Yours is cracked exactly where two of ours were cracked.

[2 for Him]

Ozz,
With the right adhesive the patch kit should work fine. When on our East coast trip we developed a leak just like yours in our gray tank. After cleaning, roughing up the surface and a coating of a plastic tank epoxy, I put two layers of Eternabond over it (hard to get smooth with all the curves) and its been fine for three years. Wish I had remembered to drill holes at the ends, but was in a hurry as I was working in a National Park campground and was afraid they would say something, never did though.
Have fun.
Tom J

[richfaa]

Leaks are common for us.We had two black tanks and one grey tank leak and now we have a leaking black tank and galley tank and maybe another grey tank.

[Recumbent]

Ozz, your photographed work will be a good reference for all of us as it seems cracks in the holding tanks are typical and espically in the neck area of the tank. The thin material used in the tanks and showers bottoms along with rigid connections and inadequate support will cause the tanks to crack.

[Illini Trekker]

I have used the same product from Amazon, but my tank that leaked was the gray tank. Ozz get you a fan ready, that stuff will kill some brain cells. Has you said drill a small hole at each end to relieve the stress in the tank. The first time I patched the crack it didn't hold. I went back the second time and used metal screen wire instead of the screen that come with the kit. I'm not sure what went wrong the first time as I did the same thing with the second patch, maybe the glue broke down the ABS screen?
My crack was around three inches long and wrapped from 6:00 to 9:00 around the drain. some have used a rubber boot to help with the growth in the tank as it fills up. Wish there was room between my black and gray tank for a boot but there was only one way to do that remove the tank or tanks. Put it on heave good luck!

[berridge]

I have used the Plasti Mend and have found it works well. My leak was at the top of the galley tank where the drain from the sink enters the tank. While I had the belly off I added two braces to try to limit the sag as there is no support for this tank. It is merely suspended from a lip along the two sides. I gave it a real test this fall when I had to drive 2 miles from the campground to the dump station with the tank 3/4 full. The repair held.

[scductman]

When I repaired my front galley tank I made 3 4" wide T braces and put one under each tank from side to side with 1" foam on top of the steel braces to protect the tank. I did the back galley tank later. Will is right they are mounted by the top flange only. I don't worry now if I have to pull to a dump station with them full now.
Bobby

[Thunderman]

I had a small leak in the galley tank.I was able to drill a small hole at each, then followed instructions and used JB Water Weld with success.
Another individual was having trouble finding the right product for the repair. He made a pile of shavings from PVC pipe then mixed the shavings with the glue used to put PVC pipe togather. He then used this mixture to seal the leak.

[patbarton]

My galley tank leaks when almost full, probably a crack near where the water goes in. The specs say 38 gallons, but it seems like half that. I must run a lot of water when I do dishes.

One day when I've fully recovered from snaking coax under the trailer for the rear-view camera, I'll tackle the leaky tank.

[richfaa]

Yes the galley tank fills fast. We keep it closed because of the nasty stuff that can get inthe tank,Since we are nearly always on full hooks we dump all tanks about every other day. we definitely have a leak in the black and galley tanks. It occurred between leaving Ohio and arriving in Florida and we are certain it was a big dip in the road in N. C in a construction area that did the damage.

[simonsrf]

quote:Originally posted by Thunderman

I had a small leak in the galley tank.I was able to drill a small hole at each, then followed instructions and used JB Water Weld with success.
Another individual was having trouble finding the right product for the repair. He made a pile of shavings from PVC pipe then mixed the shavings with the glue used to put PVC pipe togather. He then used this mixture to seal the leak.

This sounds like it could be a good solution, but I beleive the tanks are ABS plastic and not PVC.

I used a similar product like the one Ozz shows and it worked well. My problem was caused by a bad mold (circular) mark on the bottom.

[Desert RVer]

Richfaa,

Haven't you had your black tank replaced twice in the past and your galley tank once in the past? And now you have leaks again?

[richfaa]

Black tank twice and grey tank once. We now have another leaking black tank and a Galley tank. We are sure these failures are due to a really big dip in a construction zone in N.C on the way down to Florida.

[Desert RVer]

quote:Originally posted by richfaa

Black tank twice and grey tank once. We now have another leaking black tank and a Galley tank. We are sure these failures are due to a really big dip in a construction zone in N.C on the way down to Florida.

Wow, it would seem to me that eventually the manufacturer needs to belly up to the bar.