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Old 07-24-2018, 10:13 AM   #31
Wes Tausend
Junior Member
Join Date: Sep 2013
Location: Bismarck, ND
Posts: 25
Great thread!

Thought I'd add my two cents since I eventually found a bit of additional info including some waste-tank history. I apologize for the length but I wanted to be thorough.

Our former 2004 Cougar 29RLS mostly gave us great service because we loved the floor-plan and we felt it was fairly well designed. But there were some things that could definitely have been improved... and the waste tank system was one. Our black tank developed a nasty leak after one of the older kids got hurt, and we left a camp in a hurry without dumping first. It leaked into the heated underbelly (ick) which fortunately consisted of screw-on panels. There was a 3" crack on the bottom near the outlet.

Ack. My first desperate thought was to find out how to repair plastic. Our dealer suggested a local plastic repair facility. I stopped by and the facility insisted they could repair any plastic, good words to hear. The gentleman said the tanks were most likely made of ABS which is easy to repair. The kind fellow also pointed out another insight that made a lot of sense.

When these black ABS tanks are manufactured, they are made in two tub halves, top and bottom, which are then mated later. The blow mold operator is supposed to lay the hot sheet between the single set of heated forms and partially blow it into the tub shape we are familiar with. The proper procedure is to partially inflate at first, release the pressure, then re-inflate the tank the second time to full shape. The reasoning is that the form will stretch the sheet material more evenly when this is followed.

But as usual, getting in a hurry, poorly trained operators tend to try to blow the tank in one fell swoop. It seems to work for them and is quicker, but they don't realize the big picture. This causes the material near the bottom to be way over-stretched. The material is then much thinner on the bottom than sides. This unknowing error is especially bad, as the very worst stretch is that around the extra bulge to which the outlet must attach. It becomes very thin and weak. Training: I have a philosophy about this sort of thing.

Poor training is poor management and that is likely where the fault lies... with management not relaying the big picture as usual. For those of you in management, let me hasten to add, the buck always stops there. Employees average out and can be considered all the same, company-to-company, during hiring. But a great company ideally has great management... and they take a team approach rather than adversarial, us vs. them. They like and respect their employees, treat them with honesty and expect the same back. Under good leadership, most well trained employees rise to the occasion and the incorrigibles are weeded out. This simple principle of courtesy can not be overemphasized. Product value only rises with teamwork, the company continues to do well and everybody wins, including the customer. And we earthlings are all customers of one another.

Greatly impressed by the local repair facility, I made a joyous deal to bring it over the next day. My tank was cracked right under the "weak" outlet attachment point, probably from bouncing while full. Sure, the tank is well supported around the thick perimeter where it has been mated. The un-stretched plastic is full doubled-up thickness here. Nearby, away from the tank, the gate valves were also very well attached. So the crack would have been the flex point to the secure dump pipe as the entire bottom bellowed out with each bump I hit. No wonder it broke.

Unfortunately there was a great misunderstanding on my part. I brought the camper. The appalled repair facility expected the pre-cleaned, removed tank. Embarrassed and disappointed, I went home to ponder the next move.

The prospect of removing the tank seemed a major operation to me. I'm not sure the vent pipe or toilet is not somehow attached to the tank or difficult to re-assemble. OTOH, there is a possibility that both up-pipes are merely inserted into holes cut in the top of the tank and the tank may drop right out after removing cross braces and unbolting it and slip right back in later. Still, I thought I'd try an in-place repair first.

After a web search, it turns out that the reason ABS is so easy to repair is that the "glue" that melts and welds black sewer pipe also melts and welds any other ABS plastic. And it comes in three viscosities... thin, medium and thick. The glue difference is how much ABS plastic is dissolved in the mix. One can make thick glue by adding enough ABS shavings to thin glue. Or as I did, I found all three mixes at Menards and maybe other hardware stores also carry this convenient selection. I bought the thick stuff since I would be working overhead under my camper.

Remember I said it was fortunate that my camper belly was made of removable black panels. Staying more-or-less out of the way, I fully unscrewed two of them and partially another. I flushed icky particles from them with laundry soap, a push broom and a hose right in my driveway and moved them safely out of the Dakota wind to dry. I rinsed residue off the black tank bottom and remaining panels too, then let them dry until the next day.

Considering the original tank material was probably over-stretched, I added several layers of fiberglass reinforcement to strengthen the area. I used thin fiberglass tape that is designed for gypsum wallboard seams, since I had some left over, but any fibrous patch material will do if it can be saturated easily. Even embedded cotton cloth would be better than nothing. The glue has very limited tensile strength alone, probably no better than the overly thin tank area itself. The porous tape I used also allowed me to gob more on without dripping (as much) and it does dry somewhat as you are using it, allowing a layering method. I confess I liked the smell of the glue better than sewer smell.

The next day, after the repair was dry, I began to add ordinary additional galvanized plumbing strapping to support both the repair area and across general waste tank bellies. I formed a 'Y' section to cradle both the outlets (black & gray) and padded all straps with surplus seat belt webbing. That is when I noticed the 3/4 inch angle iron that supported the panels was also cutting into my tank bottoms, since one angle edge was aimed up and barely cleared. I imagine the cutting was from the bellowing during bouncing when the tanks were near full. It looked like it was almost half through already. Next I fixed that, I think.

To fix the vertical angle iron edges, I added lengths of 1/2 inch plastic water supply pipe slid over the edge. I split the pieces of pipe and let them naturally clamp over the iron angle edge, rounding it out. Then I also split some automotive rubber heater hose and let that grip over the top of the plastic supply pipe to cushion any plastic-to-plastic (tank-to-pipe) contact. All appeared it would stay in place on it's own. The assembly already touched the tank bottoms now. My hope was that that would be more than sufficient.

I never had any more trouble with the tanks and I hope the dealer (with which I traded) sold the next guy an improved, more endurable product because of my efforts. Our Keystone 29RLS Cougar travel trailer was in good shape and sold within a week.


2004 2004 294RLS TT
2000 F-250 7.3L CC
2000 Excursion 6.8L
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Old 07-24-2018, 12:58 PM   #32
travelin texans
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Location: Picacho Peak Rv Resort
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Originally Posted by itat View Post
My TT is not a Keystone or even a Thor Industries make, but you’re comment about quality across the entire industry is probably correct. Factory support after the sale is vey important as is a a good local dealer or RV repair shop in the event you have a problem you can’t fix yourself. Of course, RV forums like this one are helpful, too!

There are several RV parent company manufacturers out there besides Thor. Forest River makes mine. I think Grand Design is independent?

BTW, I’m here on the Keystone Forum because we are considering a Keystone Cougar 5er as our next camper. You read about many of the same problems on the Forest River Forum although there are also many, many posts about good factory support there.
Not to get off topic, but Grand Design was sold to Winnebago about 2+/- years ago, so no longer independent & Thor has recently acquired Jayco.
So not many, if any, independents left.


Danny & Linda
Fulltime since '08
2013 Redwood 36FB (FOR SALE)
2013 Denali 3500 DRW D/A
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