Fiberglass Rear Panel Bulging

[Comptech]

Hi,
While I was installing my new LED tail lights I noticed that the rear outside fiberglass panel bulges out on the left side. On the rear of my 5er is a ladder on the right, a rear window in the middle and the tail lights on either side. When I push on it with some force it goes back flat. It seems to be under some strain, maybe it was cut too big and forced in place by the side mounting? Is it difficult to remove the sides to see it it releases the tension? It really affects the new LED tail light on the left as it makes it point out at an angle not straight back toward traffic. The rest of the back panel is fine, it just seems to be restricted to the left rear quadrant.
Please Advise... Should I be concerned?
I attached a PIC of what the back end looks like...

So it is hard to tell from the pic but, after reading the reply's I should not be concerned...
My biggest interest in making it flatter is to get the LED tail light to point back more straight... The bulge is second...

[therink]

Hi. The rear walls on Keystones are not same sandwich construction as the sidewalls. The rear wall is hollow with fiberglass or bat insulation versus laminated with foam in sidewalls. Based on how well it was put together some bulge, some don't. They all flex though. Unless you have water or structure issues, that may just be the way it is. My old Sydney fiver had wavy rear wall. My new Sydney has some flex but is relatively straight. If you are still under warranty, you may have your dealer look at it but unless there are other issues may just say that is normal.
Steve

[Festus2]

Steve pretty much sums it up. The rear wall of our Cougar flexes for the reasons he outlined - the rear panel isn't fastened or glued down like the side walls. It is normal for it to float and flex when pushed but it should be relatively straight without any significant bulging.

[cmssorrell]

Mine has some bulging also.


Mark

[1bacamaro]

My cougar was like that to. It's not the same as the sides.

[ROLIN JOSEPH]

Mine too has significant bulging and bothers me a whole lot.
‘therink’ says, ”that may just be the way it is”.
Really? How much more than $30,000 would I have to spend to get four good walls instead of three?

[JRTJH]

How much more would you have to spend? The $80 Keystone fifth wheels are constructed with floating rear walls (those that aren't toyhaulers) so you'd have to go up about 3 times what you paid and then, no guarantees.

[ROLIN JOSEPH]

Well John, I guess the $15,000 seven year old Jayco I just traded in for my Cougar was a real good deal, because for that price, I enjoyed 'four' good walls.

[therink]

I currently own my second Keystone Fifth wheel (both with floating soft rear walls). So far I have been satisfied with Keystone quality. The rear wall in my first was a bit wavy, my second not so much.
Fwiw, my buddy has an 08 Jayco fifth wheel with a hard rear wall which is nicer, but has had delamination on the entire right side of the rear wall since year 3. Still haven't found the leak source. All brands have their ups and downs. Many brands build their rigs with the soft rear wall construction. It has very little bearing on the structural quality. I do agree Keystone could do a better job on some units when putting these walls together. I just made sure my latest rig didn't have a wavy wall before I bought it.
Steve

[JRTJH]

Originally Posted by ROLIN JOSEPH

Well John, I guess the $15,000 seven year old Jayco I just traded in for my Cougar was a real good deal, because for that price, I enjoyed 'four' good walls.

And your Jayco wasn't built by Keystone. In the Keystone product line. All the RV's are constructed with a floating rear wall (except toy haulers). As stated, there is no structural degredation caused by the bulge. Have you discussed your concernes with your dealer? There may be a remedy that he can help you with. Of course, I'd be reluctant to disrupt the assembly line components and their seals without good cause. Remember the dealership will most likely reuse the moldings, windows and fixtures from the original rear wall. If any of them are bent or otherwise damaged in removal, they may not fit properly and/or "look right" once reassembled with a new skin that doesn't bulge.

[ROLIN JOSEPH]

No John, I have not yet discussed my issue with the dealer because I just noticed the bulge. I've had the trailer since last spring and the rear wall in question seemed perfectly fine until a few days ago when I noticed this bulge that occupies about a whole third of the back wall. Unfortunately, I have no windows or anything other than marker and tail lights to hold the filon in place on the 21RBS
I recently replaced the Bargman tail lights for Command Electronic (diodes) and installed them with larger screws because they seemed too lose. At that time the wall was still fine.
Then the cold came, ....and bingo....very visible bulge. Must be the contraction of the aluminum studs.
I must admit, you guys have calmed me down a lot by explaining why no adhesive is used here, and it all makes a lot of sense.
The back wall is a real 'eye sore' but, 'it is what it is'

[JRTJH]

I obviously haven't seen your RV and can't give you any objective advise on what may or may not be wrong with the bulge that you say appeared after things cooled down this fall. The only difference, from what you have shared is the installation of the LED tail lights with "larger screws because they seemed loose". Is there any possibility that the lights may be leaking since that replacement and the bulge is related to water damage caused by the leak around one of the lights?

[ROLIN JOSEPH]

No. The bulge is under the marker lights and free floating almost the whole width of the trailer and not as far down as the tail lights.
The new tail lights have a very healthy dose of clear silicone sealant.

[JRTJH]

Joseph,

That sounds great! The only other thing that I can come up with is that the original tail lights may have been screwed into studs and when you removed them, you didn't contact the studs with your new screws. I'm certainly not insinuating that you did something wrong, rather just trying to think of issues that may have caused a trailer that's a year old and never had the issue to suddenly have that kind of bulge. The only common thing seems to be the tail light installation.

Here's hoping there's nothing significant going on, but for a bulge like that to suddenly appear seems suspect. You say you got the trailer "last spring" so it's already been through one winter without the bulge, is that correct?

Also, have you checked the rear molding above the clearance lights? There is a "J" shaped molding that ties the roof membrane into the rear wall. It's held in place by about 10 or 12 screws. The factory uses DICOR sealant to seal that molding to the EPDM and to the filon rear wall. Also, each screw is coated with DICOR to prevent leakage. If you haven't been on the roof to inspect that molding carefully, check there and also check each clearance light carefully to make sure the sealant is intact.

The bulge may not be water related, but I'd urge you to make "absolutely positively for sure certain" that there's no leak in those two areas.....

[ROLIN JOSEPH]

Two heads are better than one. I appreciate your input very much and apologize for my previous sarcasm.
The new tail lights are very sturdy and dry.
We towed the new trailer home last March and never noticed a bulge.
Now that you have enlightened me on how this rear wall is put together, I am really hoping that when things warm up again, the frame will expand again and the Filon will have the space to relax flat again.
If that is not the case, I fear that the 1000km I put on it this season has shaken something apart and that will cause more problems with rain water getting in. So far there is no sign of any water damage anywhere that I can see.
I will make another trip to the trailer storage area and check the rear roofline, markers and all screws up where you suggested. Thanks a lot.

[JRTJH]

Generally, the framework is fairly stationary and doesn't expand with heat or shrink with cold enough to cause a bulge. The filon will expand and contract enough to cause "oilcanning" or bulging between fasteners. BUT, it would seem that now, the filon would be contracting and smoothing the bulge rather than causing one. I'd expect the bulge to get worse with warmer weather.

I can understand your concern about the issue and I'd be frustrated if I thought I was in a situation where I had a problem with my RV and couldn't find the cause. No harm done, but I'd strongly urge a very careful roof inspection before it gets too cold.

[ROLIN JOSEPH]

Well John,
I made another trip to the RV storage and checked out the roof line and other points of possible water entry before the winter and everything looks nice and tight. The trailer is not even a year old.
The good news is that the bulge really is not as bad as it seemed the last time I saw it! I checked out many other Keystone products while I was there and they all seem to have as much of a bulge as mine does.
So I guess the biggest bulge was in my head. What can I say...I tend to panic when I pay good money for, (what seemed like), shoddy work.

[JRTJH]

I'm glad things don't seem as bad as you first thought. I think as long as the sealant remains intact you'll be just fine.

[SOVACRANE]

My company purchased a new 2020 Outback 341-RD in January, 2020. We were not able to do our walk through till yesterday. The camper was still at the dealership until we could do the walk through and take delivery.

During our exterior walk through i notice that the rear panel had a large bulge in the center from top to bottom of approximately 1- 1/2". To say the least I was shocked that such a nice unit would have such a poorly constructed wall that looks AWFUL!

I told the Dealer that the unit was unexceptable, they called Keystone and talked to a person that handles issues like mine. I listened to what he had to say and was very disappointed with how condescending he was concerning the rear wall construction. long story short he said "that's how we build all of them" I answered "Why" this looks awful, so your telling me that this is the best you can do? he replied that's just how we build them.

Fortunately my dealer said that they will do everything they can to make me happy. Knowing what I know now I would never had purchased this unit just because of the lack of quality, workmanship and design of the rear wall. I feel that 40K buys 4 straight walls without bulges not just 3.

Now, I am totally relaying on Keystone to step up and do what is right through the warranty process.

Just to make sure, the dealership had hundreds of units and I looked at all of them and not one unit looked as bad as my brand new 2020 never be off the lot unit.

Keystone need to fix this problem ASAP!

[chuckster57]

First off welcome to the forum. I’m sorry your so dissatisfied with the unit your company purchased. I must ask, did anybody look at the unit PRIOR to purchase?

What are your expectations from your dealer/Keystone? I understand your frustration, and I hope the resolution is satisfactory to both.