Good grief... another trailer's saggy rear

[laducky]

Hi guys,

Here's the latest development in my Airstream saga- I took off the trim to check out the sagging/leaking issue. The wood was almost directly exposed to the elements but somehow isn't falling apart. The rust seems to be only surface, so that's good. And it's like Charlotte's Web up in here! Thankfully no evidence of larger trailer residents. Plowing through all the information on the forums to figure out how to combat this... I'll keep you posted.

[dbj216]

Hi laducky; Have you done the "Airstream Dance" on the bumper of your trailer? This is a good test for rear end separation. Okay, get ready. Stand on the rear bumper and steady yourself. Start to bounce up and down like your are getting ready to do a swan dive. Watch the joint between the exterior skins and the frame rails that hold your bumper up. If you see a gap open up as you are springing up with your legs, then you have rear end separation. This means the shell and c-channel is not attached to the rear frame angle iron due to rust and floor rot.

Seeing plywood subfloor when you removed the belt line trim does not surprise. Maybe the belly pan material covers this area? Frame rail rust weakens the frame rails aft of the axles causing frame flex.

Do the Airstream Dance and if you pass, then maybe it isn't all bad. California and Southwest Airstreams are known for less rust and rot. By the way, rear end separation is completely repairable, maybe better than new.

David

[laducky]

I have done that (and felt incredibly stupid while doing it haha!) but the whole unit seems pretty solid. There is a definite droop especially felt inside in those couple of feet in the rear of the trailer when you're walking in what would be the bathroom area. I can't believe the wood hasn't completely rotted out to the point of pulp like it did in spots in the front. The rust on this trailer has been minimal considering its age (yay cali!) so it has one saving grace I believe this could have definitely been worse but I also want to take care of it and make it better than original for future use.

Right now it's parked during restoration but once I start putting some miles on it I understand an investment of axles and make sure everything is balanced and happy will keep it from being a giant rolling diving board in back. Plus I can't start building up the bathroom and then try to make the flooring/frame even retroactively!

[dbj216]

I hope someone took a video of you bouncing on your bumper. Maybe posted on You Tube? "What's this man doing?"

Maybe it's time to pull the belly pan from the bumper to the axles and see what's under there. It's a messy job, but not hard, and not damaging to your trailer. Just drill out the rivets. Then you can judge how well your shell (C-channel) is fastened to the rear most cross member. Rotted flooring or rusted out cross member needs repaired. And you can inspect your frame rails for cracks or buckling behind the axles.

Possibly the wood floor has rotted away enough it is not well supported by the rear most cross member. It was in my 66. This may account for your bath floor sloping down hill.

I guess I would want a look - see.

David

[laducky]

haha more like "what was this woman doing??" haha

I've started the process of taking off the banana wraps and I only have a few pictures so far... I'll keep working and post more in the next few days. So its normal to see the wood once you take off the trim? That strikes me as completely bizarre since the trim is not caulked or weather sealed at all! That last picture attached shows a whole ecosystem growing in that little nook it creates against the skin draining down into the belly. I'm not an engineer, but I can't believe it was lapped like that.

I'm also wondering how to drop the tanks. That looks like quite a hefty one man (or one woman) job. Is there a method to getting them down without crushing myself in the process?

Haha I love the forums. Nothing like starting out the day talking about sag, waste tanks, and crawling under trailers to drill stubborn rivets overhead!

[dbj216]

I'm embarrassed. I didn't know you were a woman! Forgive me.

Old Airstream basements are kinda dirty. But nothing that won't wash off. My 86 is built with the lower wrap overlap just like yours. I just figure rain water is going to get into the basement and puddle on the belly pan. So I polyurethaned the bottom side of the subfloor, installed the insulation, and drilled small drain holes in the belly pan so the water can drain out and I get a bit of circulation down there.

Your tanks are plastic and not too heavy empty, like 25 lbs or so. They are attached to the plumbing drain lines, maybe the toilet flange, and the vent stacks. There may be a big old pan bolted to the frame that protects and insulates the tanks as well as provide a floor for them to rest on.

I'm anxious to see a picture of the rear support that the rear of your shell is bolted to. Here is a photo of my 86. It has rust holes in it from sitting in a wet basement for many years. Water just pours into the bumper storage compartment and puddles all the way to the tank pan.

David

[janeinthemtns]

Still trying to figure out how to keep track of threads. I have an 31' 85 Excella. How are things in Pacifica? Lived there and Montara for years. Now in north central New Mexico.

[laducky]

Pacifica is beautiful, but the days are short and cold right now, and I'm mad at my trailer :P Haven't gotten much progress on the sag yet since I've been dealing with the current leak crisis (fix one, find two more) and electrical so that's been keeping me busy. I'm just frustrated I'm going to have to figure out frame issues and maybe drop the tanks before I can start building the inside again.