Subfloor replacement with surprises

[rowesean]

My wife and I are renovating a 1976 International Sovereign 31' we bought recently. After removing the prior finish floor, we discovered we need to replace the rear piece of subfloor. After researching the forums and blogs, I have gone with a shell on approach since just the most rear piece needs to be replaced. I got the interior skins off today, and discovered something I was not expecting:
1) the elevator bolts are upside down. From other pictures I had seen I was assuming the heads would be up (since you are supposed to remove the belly pan to get to the nuts). However, as you can see from the picture I attached, the shaft is up and bent to keep the nut on. I guess that if I cut or bend and remove the nut, it will just drop into the belly?
2) there are 2 larger bolts (one is on the left in the picture) that are in the rear and have a rusted plate they run through. What is the purpose of these bolts?
Anyone else encounter this?

https://picasaweb.google.com/lh/phot...eat=directlink

[steve46]

The bolts you see are not the elevator bolts, rather those you show hold the "radius channel" to the floor (and the larger one for sure, to the frame)--the same structure exists in the front of the Airstream. The elevator bolts you may have not yet uncovered, they sit "inboard" and not around the perimeter. I hope this helps.

[aquinob]

You will need to drop the belly pan, at least in the rear, so go ahead and do that, it will make things a lot easier.

The larger bolts most likely bolt through to the frame itself. There should be a piece of angle iron between the main frame members and the other bolts go through that, through the subfloor and then through the c channel. That big piece of angle iron is probably mostly rusted away by now. Take a look at my blog and you will see what I'm talking about. I tackled this job the first year I had the trailer.

This is a very poor design on Airstreams part. Water just funnels back to that area and the sheet metal tends to push it up against the edge of the floor where it rots. They also use steel up against aluminum which promotes oxidation of both the steel and aluminum (can you say battery, I'll bet you can) due to dissimilar metals being in contact.

The elevator bolts are essentially self tapping screws that go down from the subfloor through the frame and cross members. They have no nuts on them and are phillips head.

[Belegedhel]

Your surprises are likely just beginning! As they say, "a vintage Airstream is like an onion--the more layers you peel off, the more you cry."

Anyway, the upside down bolts you see are the norm. If you grab them with vice grips and work them back and forth once or twice, they will snap off. The rusty piece is the rear hold-down plate. The plate itself is riveted to your rear center section of skin and bolted to the rear most cross member. The hold down plate is likely to be rusting away, and your next surprise is likely that your rear most cross member is going to be disintegrating as well. If you are lucky, the rivet holes in the back aluminum panel will be intact--mine were tearing out and horribly corroded. I had to replace my back center panel and the last 3 ft of frame with the last two cross members.

As mentioned above, you will need to drop the rear banana wraps at the very least in order to do the floor replacement.

good luck!

[lstepp2]

I have not looked at my Bus's flooring. But I must ask the same question I ask about a 'Rubber Roof," Are RV builders crazy. I located a place in northern California that has rolled Aluminum that is 10' X35'. After finish the very expensive repairs on my 1995 Land Yacht motorhome I am going to have a metal roof put on the bus. School buses, Semi-tractor trailers have steel roofs and they do not leak. They also require minimal maintenance.
Once I replace the Rubber with a metal roof, I will inspect the flooring. All Subflooring should be one solid piece of metal, even if it is welded together the way auto flooring is constructed. Unless you are driving a bus or pulling a travel trailer in the snow and salt the metal floor should outlast your grandkids.

[Chuck]

Hate to disagree with Bob, here, but elevator bolts are not self-tapping screws; they're 1/4-20 carriage bolts with flat heads...and they do have nuts.
fwiw, my hold down plate was not rusted away...it was very "rusty", but all surface crud and pits. Its still a very solid, heavy piece of metal that you do not want to drop on your toe. (I wire-wheeled it down, and por-15-ed it, and its going back in).

[rowesean]

Thanks for all the feed back! I ended up cutting all the bolts with a reciprocating saw and they came away very easily. I then cut the middle section of plywood out, removed it, and cut the what I now know are the elevator bolts into the frame with the saw as well, and pulled out the side pieces of plywood. That left the frame exposed which is rusted but fairly well intact. The rear crossmember is very rusted, as you can see in the picture, as is at least the exposed piece of angle iron. Looking at it I figure I need a new rear crossmember, maybe new angle iron. I have some guys from a local machine and welding shop (because this is one thing I have no experience with or tools) are coming out to look at it today or tomorrow, so hopefully they can replace/repair the necessary pieces so I can re-install new subfloor and finish up the rear. Till then, I guess I'll work on the bathroom replacement.

Sean
https://picasaweb.google.com/lh/phot...eat=directlink