Classic Exterior Wall Problem

[jestal]

I discovered that the exterior wall above the rear wheels on the driver's side was loose and bulging out. I've noticed some misalignment with the rear cargo door off and on for some time and just dug into it. This section of wall is only about 16 inches tall from the top of the wheel well skirt to the bottom of the slide.

At assembly Entegra drives (small) screws vertically thru the aluminum angle at the bottom of the exterior skin into the steel frame to secure the wall. My screws had all loosened/broken and fallen out but were trapped in the gap to the wheel skirt. As they worked around at an angle they would push the wall out and hold it away from the structure causing the bulge. The screws had only pierced the aluminum angle iron and never touched the frame to hold anything.


I removed the wheel skirt by removing the lag screws from the backside that hold it in place. With the top of the skirt tipped out it is easy to see the bottom of the exterior skin and the aluminum angle. There are stacks of plastic shims in about 6 spots on top of the aluminum angle spacing the angle to the frame. The screws had never penetrated the frame! They were just thru the aluminum angle iron and into the plastic shim packs missing the frame outboard completely. The wall had been loose since built but the tension kept it in place I guess....until the shim packs turned sideways and the screws started falling out to be stopped by the top of the wheel skirt trapping the wall out board.


I left the bottom screws in the wheel skirt in place...just loosened them...so the skirt could tip out and not totally loose position. Plus, some moron had run wires along the back side for extra turn signals….. so removing it entirely involved disconnecting wires and/or removing lights.


With all the screws out it was relatively easy to pull the wall in line with a row of big clamps and blocks of wood. I then made sure I was far enough inboard to hit the frame and drilled vertically thru the aluminum angle on the skin and thru the steel frame. I installed some 1 inch long self tapping/threading stainless screws thru the predrilled holes. I predrilled 3/16 and used 1/4 self drilling screws. In most places I found I had to drill a little deep and actually went thru the plywood floor and into the aluminum wall framing based on the chips. I did not want to break off one of the self tappers due to running into something not predrilled.



The screw heads are visible in the gap above the wheel skirt but painted black they are invisible. AND the wall is now straight and tight and aligns with the cargo doors, etc.


The wheel skirt was relatively easy to get off once you locate the correct lags holding it from behind. Drilling the vertical holes thru the steel frame was the most difficult part.


The aluminum angle at the bottom of the exterior wall skin was predrilled in spots but all the predrilled spots missed the frame to the outside so I had to go well inboard of them to find a solid connection.


Many thanks to Mark at S&S for talking me thru this repair. This is not an isolated case apparently and he was very familiar with how to fix it. Very helpful and freely shared knowledge and instructions on how to do it and it pretty much went exactly as he described so hats off to him for his help, patience and selflessness with his knowledge!


Any one with a classic might want to check this area of the exterior wall. Just the section above the wheel skirt on the driver's side to make sure it is attached.

[brobox]

Nice share Al. The moron the strung wires in the wheel wells for additional turn signals sounds like something I would do.

[Johnnypac]

Originally Posted by jestal

I discovered that the exterior wall above the rear wheels on the driver's side was loose and bulging out. I've noticed some misalignment with the rear cargo door off and on for some time and just dug into it. This section of wall is only about 16 inches tall from the top of the wheel well skirt to the bottom of the slide.

At assembly Entegra drives (small) screws vertically thru the aluminum angle at the bottom of the exterior skin into the steel frame to secure the wall. My screws had all loosened/broken and fallen out but were trapped in the gap to the wheel skirt. As they worked around at an angle they would push the wall out and hold it away from the structure causing the bulge. The screws had only pierced the aluminum angle iron and never touched the frame to hold anything.


I removed the wheel skirt by removing the lag screws from the backside that hold it in place. With the top of the skirt tipped out it is easy to see the bottom of the exterior skin and the aluminum angle. There are stacks of plastic shims in about 6 spots on top of the aluminum angle spacing the angle to the frame. The screws had never penetrated the frame! They were just thru the aluminum angle iron and into the plastic shim packs missing the frame outboard completely. The wall had been loose since built but the tension kept it in place I guess....until the shim packs turned sideways and the screws started falling out to be stopped by the top of the wheel skirt trapping the wall out board.


I left the bottom screws in the wheel skirt in place...just loosened them...so the skirt could tip out and not totally loose position. Plus, some moron had run wires along the back side for extra turn signals….. so removing it entirely involved disconnecting wires and/or removing lights.


With all the screws out it was relatively easy to pull the wall in line with a row of big clamps and blocks of wood. I then made sure I was far enough inboard to hit the frame and drilled vertically thru the aluminum angle on the skin and thru the steel frame. I installed some 1 inch long self tapping/threading stainless screws thru the predrilled holes. I predrilled 3/16 and used 1/4 self drilling screws. In most places I found I had to drill a little deep and actually went thru the plywood floor and into the aluminum wall framing based on the chips. I did not want to break off one of the self tappers due to running into something not predrilled.



The screw heads are visible in the gap above the wheel skirt but painted black they are invisible. AND the wall is now straight and tight and aligns with the cargo doors, etc.


The wheel skirt was relatively easy to get off once you locate the correct lags holding it from behind. Drilling the vertical holes thru the steel frame was the most difficult part.


The aluminum angle at the bottom of the exterior wall skin was predrilled in spots but all the predrilled spots missed the frame to the outside so I had to go well inboard of them to find a solid connection.


Many thanks to Mark at S&S for talking me thru this repair. This is not an isolated case apparently and he was very familiar with how to fix it. Very helpful and freely shared knowledge and instructions on how to do it and it pretty much went exactly as he described so hats off to him for his help, patience and selflessness with his knowledge!


Any one with a classic might want to check this area of the exterior wall. Just the section above the wheel skirt on the driver's side to make sure it is attached.

I have been re securing and aligning body panels since 2015. The factory repaired some panels but reinstalled wheel well panels crooked. I had to realign them. I just noticed the r/r wheel well panel didnt look right. It turned out it was very loose along the top. To my surprise the entire length of the panel was only secured from the factory with 2 self tapping screws going through the steel channel into the fiberglass wheel panel. This panel is at least 8 ft long and only 2 screws, 1 at each end. Of course eventually the self tappers stripped out of the fiberglass panel. I had to drill two new holes through the steel and reinstalled self tapping screws to secure. We are traveling now so when we return home I will secure the panels the proper way. Another area for a second look.

[jestal]

John, I had two of the self tappers used to hold the skirt to the chassis stripped also. One was stripped originally and barely holding and the other stripped when I put some tension on it. I replaced with slightly larger lag screws. The self drilling/tapping screws are just not designed to go into wood or plastic or fiberglass a they remove too much material with the drill point. Steel leaves enough for threads to cut but the wood/plastic/fiberglass does not have the strength. I cannot believe how many places Entegra uses the self drilling/ screws improperly into wood/plastic/fiberglass.


if I lived closer to Middlebury I would volunteer as an ad hoc fastener engineer for them......then again...….

[Johnnypac]

Not to many ways to attach theses panels but the way they were is really crap. I plan to secure them by adding small metal plates to fiberglass panels securing the four corners with self tapping screws. Then passing a sheet metal screw through the metal channel into the attached metal plate. This way the securing point will be into the metal which should not strip and the plate should hold much better with four screws securing it to the fiberglass.

[DeeGee]

Having worked with fiberglass in a situation where things Really Cannot Fall Off (an airplane) I feel confident that I can fasten anything to fiberglass. However, Entegra (nor any other manufacturer, as far as I've seen) does it right. You never trust a screw into fiberglass. Always bolt through, with a noncrushable plate in the area, when there is stress involved. For lightweight applications, I have installed nut plates with rivets, then screwed into those.



For stress areas, the filler between the inner and outer fiberglass layers is removed, a metal plate is put in, and the area glassed over, with more layers than the original and a known amount of overlap. Then you have a decent hard point. Of course, airplane fiberglass is typically woven cloth layers are various angles to each other, with a core that us usually foam, which is crushable. Thick glass shot from a gun, as a lot of RVs and boats use, is a bit different, but you still need embedded hard points for anything important.