Holding tank removal Ultimate Advantage

Karl Evans · 09-28-2014, 03:51 PM

I just got finished changing out both valves and the Calder couplings on my 2000 Ultimate advantage holding tanks. I now have a leak at the 3" nipple that comes out of the bottom of the Black tank (nearest outside) at the very bottom. It appears to be ABS, seamed to the plastic tank and the seam is cracking and leaks. There is evidence on the Styrofoam on the floor of a leak going on for some time. Whatever was in the tank must have slowed it enough to never see any signs of leaking underneath. Now that I flushed everything before starting the valve replacement the clean water leaks fairly rapidly. I see that the 3" nipple on the gray water tank is made of the same material as the tank. It may be one of those spun in fittings such as Ardemco does on their tanks. I can see that I am up against having to remove the black tank to replace it. Has anyone on here done this before? Any steps or links or pictures would be helpful. I am back in there to where I was when I removed the manifold with the Y that went to both tank valves. i'm guessing the upper panel with all the valves, switches and hose hookups comes out next. Any help on this would be appreciated since I am totally unfamiliar. Also any source for a new tank would be helpful. I don't see it in Mobility RV's catalog. I found it on a Winnebago parts site 128993-01-700, but there was no information how to order from that site.

Thanks, Karl

cbeierl · 09-28-2014, 04:00 PM

Can't help on the removal, but if you work with Mobility RV or Lichtsinn (or most any Winnebago/Itasca dealer) they should be able to order a tank for you. Since Winnebago makes all of their own tanks I would assume that they would be able to provide one.

ChasA · 09-29-2014, 08:12 AM

I have heard of plastic welding. Maybe there's a place near you that could weld it.

Ray,IN · 09-29-2014, 08:00 PM

Yup, any good auto body shop can plastic weld if the area is accessible to them. They have filler rods for all types of "plastic". It's basically a spot-area ultra-heat gun that melts the material back together while adding filler rod. Even Harbor-Freight sells one(with filler rods)for home use.

CC38EL · 09-29-2014, 10:32 PM

Sounds like we had the same tank guy make both our black tanks. I had the same issue with my black tank. I was replacing the waste gates and noticed a long term leak. Cleaned it up and it started leaking faster. Tried several glues without success. Even tried Eternabond....no joy.

After I took off the bottom panel and the small panel with the pull cables on it, I then took off the panel in the pass through compartment to get the opposite side of the nipple. The nipples appear to be welded in place and the welds are where it was leaking. Took it to an RV dealer in Virginia who happened to have one of those 'RV gurus' on staff who can fix anything. It looks like he tried to melt the plastic and flatten it around the nipple connection. They did get it to stop leaking quickly....and in the end it would fill an 8 oz cup over a months worth of camping. Over time, since it's the black tank, enough solids have found their way into the hole that it doesn't leak anymore.

As already suggested, you're going to need someone to weld that thing in place or replace the tank. There is no glue or patch or tape that will stick to that well enough to stop the leak. Winnebago does not stock that tank and will have to make it from mold for your VIN. I don't know what you would have to remove to get that tank out. But like most things in our coaches, it seems like they made the tank, put it in the chassis and then build the coach around it. The guys at the RV dealership were not optimistic if the gurus work didn't fix the leak.

Wish I could be more helpful other than confirming what you're already suspecting. I didn't try welding.....although the RV dealer said it should work. I did not try to get a new tank. You may have good luck contacting Winnebago directly or Lichtsinn.

Karl Evans · 09-30-2014, 10:07 AM

Thanks Jim. I have been willing but not overjoyed about taking the tank out since I discovered this. I am now on the third day of disassembly. Part of what takes so long is going slow and trying to figure out how it comes apart. Getting older don't help either. I was hoping to find someone who could give me a sequence of what had to come out. I know by now there is actually another removable panel at the back of the wet bay. Accessed by lifting the fender arch, cutting the weather strip, cutting the foam block in half that supports the rear of the tank and removing the two pieces. A scissors jack under the tank helps get the foam out. It appears that the toilet and vent pipes disconnect when the tank is lowered. I should find out today. Mobility was very helpful and got a quote back to me same day. The biggest problem is a 4 week delay for manufacturing. I am going to try to spin weld a fitting in this week with a router. If it don't work I wait 4 weeks. What I don't know is will it be a piece of 3" ABS, glued into a dissimilar material again.

Karl

CC38EL · 09-30-2014, 10:49 AM

Good luck, Karl. Hope that spin weld works. Let us know how it goes.

depchief · 09-30-2014, 07:21 PM

Karl
Once you get the tank exposed, myself and others,would love to see pictures of the installation. This is a repair I hope I never have to do but a picture would be a help
If you cannot upload pictures, maybe we can email them

ABS plastic pipe is not used in all areas of the country. The black glue used on fittings is very good, possibly it would seal the crack. Hopefully available in your area.

KIX · 09-30-2014, 07:46 PM

Karl, I see that you are in CA so perhaps you may not know this. Lichtsinn is in Forest City, IA about 1 mile from the Winne factory. Google for phone # and speak with Dave in parts. He'll need your Winnebago serial # (not the VIN).
Mobility is in Hanlon, IA and their office is about 7 miles from factory. Those guys compete but neither one stocks much. Lichtsinn is a Winnebago coach seller too.....Mobility is strictly parts.
Another though is to call Winnebago Customer Service in Forest City and try to talk with Carlene Meyer. She can tell you the material the tank is made from to help with a weld. Hoe all this helps some. Good luck
I know this info doesn't help with your repair but maybe it'll help you get a tank if you can't repair what you have.

Karl Evans · 10-01-2014, 01:58 PM

Thanks for the help on this guys. I am assuming the tank is polyethylene but I can't say I really know. It is flexible. My understanding is that ABS can be glued, but polyethylene can not. If I get these pictures to post you can see the epoxy or whatever it is has separated from the tank, not the black pipe. I have the slip through fittings and driver in now. After practice on some scrap plastic I will give it a try.

CC38EL · 10-01-2014, 03:47 PM

Great job, Karl. And yep...that's exactly where mine was leaking. Great photos.

Continued good luck.

KIX · 10-02-2014, 09:11 PM

Maybe you've heard of 3M 5200. It's used extensively in marine applications requiring adhesion above and below the waterline. There's a quick set and a "standard" cure version. The standard cure takes about a week to fully cure. It's really super stuff and IU think it will bond to your tank and to ABS. You could try the quick set on a place on the tank and to some ABS. If the quick set bonds the standard cure will be even better. I know you can order the standard from West Marine online.....the quick set is available at Home deoot.
AS far as re-bonding polyethylene (PE).....years ago we used PE for gas lines. Bonding was done by heat welding. If it were me I would try the 5200. Hope this helps you.