Seneca cap interior failures

[Rustynuts]

Originally Posted by Gigjoec

i have discovered mine is having the same issue with the sides of the home...
2 questions i have ......
1 is it necessary to do the wing board mod if not showing an issue there ?
2 how is the nuclear option holding up ?

I would say if you have things apart, do it all at the same time, it won’t hurt anything to go ahead and do it. The bolt thru side wall option is holding up great, I’m going on my second season with it. I left mine exposed on the inside to keep an eye on it the first year and say no signs of movement or separation and have been on some pretty rough sections of road.

[dopplemeyr]

Hi all, when I did my wing wall installation, I noticed that water was slowly leaking in at the seams of the cap. What did you do to reseal? Also, did you take out the old caulk or just put more on top of the old?

[Superseneca]

I see so many reports of cab separation other freight liner senecas. Just wondering if the root cause is the cab to chassis flex. If the house is mounted to the frame rigidly and the cab is mounted on rubber mount to improve ride quality, I can see why cab separation is occurring. Just a theory.

[BIGPAPA1970]

So my trim finally failed while driving through the mountains in 117 degree heat. Look in the side mirror and saw half the trim hanging off. All the screws were there but the self tapping just couldn’t bite into the side. Here is my question, there was a thick butyl type sealant all over the old metal, what is everyone doing with the “nuclear “ option for sealing outside?

[Robbbyr]

Originally Posted by BIGPAPA1970

So my trim finally failed while driving through the mountains in 117 degree heat. Look in the side mirror and saw half the trim hanging off. All the screws were there but the self tapping just couldn’t bite into the side. Here is my question, there was a thick butyl type sealant all over the old metal, what is everyone doing with the “nuclear “ option for sealing outside?

Sorry to hear you are experiencing it too.

Jayco put a strip of butyl tape under the outside metal strip, tightened the screws causing some of it to be extruded out. Then they removed the excess so the cover strip would "latch" over the edges and be retained in place. Then they caulked the forward and rearward seams where the trim strip contacts the cap and sidewalls.

I put mine back together the exact same way, except it is through-bolted with #10 stainless steel bolts and not screwed with a #8 1" ferrous screw. I used the original aluminum strip (straightened out as needed) and laid a 1" wide strip of butyl tape between the aluminum strip and the body. Tightened all the bolts (about 20 in/lbs) and then cleaned off the excess butyl material and installed cover strip. I used clear Geocel ProFlex RV caulk and carefully taped one side of one strip and body to give me a nice caulk bead. Smoothed the caulk and immediately removed the tape. I let the one side cure overnight then repeated the taping and caulking on the other side of that strip. Then did the same to the other side of the rig.

[EricM22]

Wing wall question: what thickness plywood?

I'm not seeing the spec in any of the diagrams, unless I don't know what I'm looking at. Thanks.

[Robbbyr]

Originally Posted by EricM22

Wing wall question: what thickness plywood?

I'm not seeing the spec in any of the diagrams, unless I don't know what I'm looking at. Thanks.

I used 3/8" Baltic birch plywood. Very stiff stuff but not cheap.

[BIGPAPA1970]

Originally Posted by robbbyr

i used 3/8" baltic birch plywood. Very stiff stuff but not cheap.

3/8” ?

[Robbbyr]

Originally Posted by BIGPAPA1970

3/8” ?

Yes, 3/8".

I had previously done the "nuclear" fix to the outside vertical seams (through-bolted) and had constructed cover trim for the inside to cover the strip and exposed bolts and nuts. If I had gone thicker on the wing walls I might not have had room to install the upholstered cover back over the wing wall without it interfering with the trim.

I believe some owners have reported Jayco used standard 1/2" plywood on their rigs. I believe that the Baltic birch plywood is stiffer than 1/2" plywood one would get from Home Depot or Lowe's. I've got thousands of miles on my repairs now, much quieter and things are holding up well. I'm sure you could use thicker, but 3/8" is working for me.

[Rustynuts]

Originally Posted by BIGPAPA1970

3/8” ?

The key thing here is 3/8” in Baltic Birch. Baltic Birch has more plys, stronger face and no voids in any of the layers, it is extremely strong. IMO 3/8 Baltic Birch than a 3/4” CDX Fir Plywood.

[EricM22]

Big thanks everyone. 3/8" baltic birch it will be. I'm going to begin tackling it this weekend, at least get everything disassembled and the wood cut to shape.

Can't thank everyone enough for the pics and advice!