Replacing Subfloor on a 1974 31' Land Yacht Excella 500

[McilnayS]

I'm needing some advise on my first major project with our diamond in the rough 31' Excella 500. I have being searching all over the web and YouTube but cannot find anything about replacing the Subfloor on our exact Airstream model?... I did find some articles talking about this with other models and there seems to be some controversy about only being able to complete this by lifting off the shell and then other saying not to lift the shell cause you will never get it lined up correctly dropping it back down? I need to find out the truth from someone who has done this work on our model of Airstream. In addition to this, I need some clarification on whether this model of Airstream uses elevator bolts? I would also like a better understanding of this bolts and what they really do.

Thank you to anyone who can assist me with all theses questions before I start this mind boggling project.

Steve

[raphspeaks]

Hey Steve,

I have a 31' 75 excella 500, center bath. I've replaced the entire 8 feet of the rear frame and sub-floor, and just buttoning up the front 12ft of frame subfloor. At this point I could probably tell you anything you'd like to know...

Through my research lifting the 31 off of the frame isn't an issue. You'll need 3 gantries to do it right with proper bracing, but from what ive gathered, it's fairly routine as smaller trailers. I opted for the shell on approach simply because I'll plan on a shell off once my kids get a little older to help. Knowing what I know now I'd probably opt to do the shell off approach.

In regards to your question about the elevator bolts - mine were rusted to the point of not really knowing what kind of bolts they were. The looked more like a carriage bolt than anything. I replaced them with galvanized steel bolts with washers secured to the out riggers. I dont think elevator bolts are used. Feel free to link me to some docs and I'll take a look.

If you have subfloor, odds are that you have some frame damage. Have you removed the belly pan to inspect?

Do you have the factory service manual?

[sgschwend]

Both ways work, and the way AS assembles the trailer over the years is pretty much the same (taken from my experience with a 79 and 86 years).

It is really your choice, just be prepared for many hours of work. Have you done a 2000 hour project before? The shell off will take more time. The localized repair method would allow for use of the trailer between area repairs.

You can also remove the troubled sub-floor and inspect the frame without taking the belly pan off. The frame can be repaired from the top too.

[McilnayS]

Originally Posted by raphspeaks

Hey Steve,

I have a 31' 75 excella 500, center bath. I've replaced the entire 8 feet of the rear frame and sub-floor, and just buttoning up the front 12ft of frame subfloor. At this point I could probably tell you anything you'd like to know...

Through my research lifting the 31 off of the frame isn't an issue. You'll need 3 gantries to do it right with proper bracing, but from what ive gathered, it's fairly routine as smaller trailers. I opted for the shell on approach simply because I'll plan on a shell off once my kids get a little older to help. Knowing what I know now I'd probably opt to do the shell off approach.

In regards to your question about the elevator bolts - mine were rusted to the point of not really knowing what kind of bolts they were. The looked more like a carriage bolt than anything. I replaced them with galvanized steel bolts with washers secured to the out riggers. I dont think elevator bolts are used. Feel free to link me to some docs and I'll take a look.

If you have subfloor, odds are that you have some frame damage. Have you removed the belly pan to inspect?

Do you have the factory service manual?

Greeting,

I have not pulled off the belly pans yet as I have been doing as much research as I can before I start on the restoration. We picked this Airstream up for $1500.00. Not a single cracked window or any major damage to any of the body panels. We do have the original paperwork and owners manual along with the title. I feel we got super lucking finding it and getting it for that price from these crack heads. Unfortunately they did just that in it, smiled crack. I have already gutted the whole thing on the inside and that is why I'm wanting to replace the 3/4" subfloor in it so the restore will be done right.

The bolts going through the floor are heavily rusted like your sounded like. I have not attempted to loosen any of them yet.

Dropping the belly pans are pretty easy I take it?

Sincerely,

Steve

[McilnayS]

Originally Posted by sgschwend

Both ways work, and the way AS assembles the trailer over the years is pretty much the same (taken from my experience with a 79 and 86 years).

It is really your choice, just be prepared for many hours of work. Have you done a 2000 hour project before? The shell off will take more time. The localized repair method would allow for use of the trailer between area repairs.

You can also remove the troubled sub-floor and inspect the frame without taking the belly pan off. The frame can be repaired from the top too.

Greeting,

Thanks for getting back to me. I agree with leaving the shell on for stop repairs but unfortunately, we need to replace the whole subfloor due to drug use in it. I will also be doing a complete steam clean wash down inside it before installing new insulation and new wall panels.

When it comes to 2000 hour projects at home, yes I have. I built my house. But working on a Airstream and not screwing it up or causing more damage or more work I'm finding is a lot more stressful. Haha

I'm really wanting to do this right. This includes upgrading all the wiring, lights to all LEDs throughout, and installing new appliances. Although that is another tough subject within it self!? Such as to go with heat on-demand water heater or go with a standard tanks style, and what to to go with for heat? Forced air or radiant heat with regulators?!..

But I'm looking forward to getting this started. Just don't want to rush it and back me self into a corner and can't get it put back together.

Sincerely,

Steve

[fwjumper]

Sorry if I am ignorant, but why do you need to replace a wooden subfloor because of drug use? I understand and agree with your desire to clean/strip/sanitize, but I would only remove subflooring that is rotten or soft. Once you are down to the subfloor, you can clean it with anything you want. Just provide good ventilation for your safety and for good drying. If most of it is soft, then I withdraw my question. With that said, it is usually reasonable to replace flooring with the body on, unless it is badly deteriorated under the walls. Unless there has been major water intrusion, I wouldn't expect yours to be in that category. Is body off better? Probably. Is it always necessary? No.

Elevator bolts are simply bolts with thin, totally flat heads, so flat that you can install carpet over them without them telegraphing through the carpet and padding. You can replace them with other types, carriage etc, depending on your flooring choices. If you recess the bolt heads into your new subfloor you could weaken the attachment points, but with extra caution, it can be done. You can buy self-drilling/tapping flooring bolts from vintage trailer supply and others that work pretty well.

Whatever you do, don't waste your time trying to remove the existing bolts. Cut the heads off with an angle grinder or something similar. Just watch for smoke. Keep a spray bottle of water handy to extinguish the inevitable volunteer wood fires. After the flooring is out you can decide what to do with the bolt's carcass.

Good luck in your adventure. You will enjoy seeing the progress.

[Minno]

Our thread: "Little Girl Refurb" shows extensive pictures and explanations of shell on replacement of sub floor.

Kay