American Coach: Basement Rust Repair

[Meames1]

Anyone interested in following along while I repair the rust of the basement frame on our 1999 American Dream ?

While shopping for RV's I researched the American Dream on here and found that basement floor rust was a common thing to look for on these coaches. With your advice, I looked for the issue, noted it, and was able to negotiate a substantial amount off the asking price knowing I had to fix it.

Once I got the coach home, I started tearing into it so I could figure out how it was built and come up with a game plan to repair. I quickly realized that the basement floor had separated in spots as much as 1" from the frame supports ! Further investigation found that the entire floor structure was pre-fabricated much like a wall assembly and bolted to the coach frame supports. Ironically, the Spartan MM frame was like new with no signs of rust. I decided the best repair would be to completely drop the floor structure build a new one and re-attach to the uprights that I would also repair by replacing any rusted metal tubing.

I will be building the new floor structure with 1 1/2" square tubing like the original, however I will be making some small changes. All the fasteners will be Stainless Steel, not much of a price difference when doing one coach, but I can see how AC wouldn't do it. I will also be lining the bottom of the floor with .018 S/S instead of the thin Aluminum that AC used. This would stop the galvanic reaction of the dissimilar metals and what played a large part in the start of the original corrosion. I was supersized to see that AC did not paint the steel at all, I will be adding a corrosion-resisting paint.

I'll be adding pictures as I go. Any questions or advice... shoot.

[Meames1]

In deep !





Floor out and on the ground !


The white panels used on the top-side and all along the interior of the basement have been torn off here to expose the steel structure and insulation. The panels are fiberglass reinforced embossed panels readily available at Lowe', Home Depot, etc. I'll be using the same panels on reassembly including patching in where I need to cut them off the uprights to replace any bad steel.

[Meames1]

Some crappy pics of the MM frame, way up high where it belongs.

[Meames1]

Steel has been ordered. Next is to blueprint the original structure and making some plans.

[Meames1]

Started cutting the steel and laying it all out.







I haven't been doing much fab in the last year or so due to a torn rotator cuff and subsequent surgery. Feels good to blow the dust off both the equipment and me and start burning metal.

[iowaone]

Very interesting to watch. Thanks for sharing.

[Meames1]

Phase 1 complete ! All squared and welded up. Next, prep and paint with POR 15.

[Jthigh]

Definitely interested. Have the same issue with mine and curious what it will take to do the repairs. I was underneath mine the other day and found that water was getting between the panels at the top of the rear wheel wells.

[Jthigh]

Interesting to see how far up you need to go on the vertical post to get to solid material.

[Meames1]

Originally Posted by Jthigh

Interesting to see how far up you need to go on the vertical post to get to solid material.

The rear vertical support is pretty bad. They get better as you go forward. I am seriously considering removing and replacing the entire rear one. The remaining supports, I am pretty confident I can just replace the bottom tube in most and possibly just clean and paint the bottom in some. Which is a good thing as the center and front supports have the propane lines and slide bar running through them and I'm trying to not take the whole coach apart to do this repair. However, I'll do what's needed to make it right. I have to keep telling myself that it's a 20 year old coach. But, my labor is cheap
Thanks for the interest.

[Maik]

Very interested; as I do have some rust problems. It is mainly back at the water bay area. Thanks for posting and sharing

[winniman]

My friend had a similar problem with his 03 National Tropical. He redid the entire bottom structure similar to what you have done. He though the uprights were in decent shape, but after only two years, the uprights have gave way, and now he has to redo the uprights. I would suggest redoing the uprights the first time around. The areas around the water and sewage tanks are a particular concern due to the amount of weight it carries. Looks great so far. Cheers

[Meames1]

Got the frame prepped and painted. Starting the skin next, first bottom S/S and then flipping over for insulation and top FRP panels.







Removed the rear-most upright panel. It was the worst one and I'm going to completely rebuild it. This pretty much beat me up, spent about 3 hours removing it. There was a ton of sealant at all the seams, I believe the PO added additional sealant on top of the factory stuff so all the fasteners were buried etc. It will go back together much easier, but I was swearing a lot during removal .

[Jthigh]

Good to know that it bolts on as well. Thought it would have been welded on. Doesn’t look like there were any hoses or cables that pass though panels so that’s nice not having to cut slots in the panels to reinstall.