Please see BIG FAT DISCLAIMER regarding DIY safety. Also please realize that not every Interstate is configured identically - even if they are the same model and same year, they may have been built with different options, causing alterations in equipment placement. None of this procedure given below has been approved or endorsed by Airstream. Prior to beginning this work, my husband called Airstream technical support and asked if there was a service bulletin on how to repair this problem, and he was told that there was not.
You should realize in advance that, if your grey water system proves to be constructed like ours, then it was a permanent install never intended for removal (an exceptionally poor design). If your three lines have already sheared off the tank as ours had, that's a moot point. But if one or more of your lines are still attached, you will shatter your remaining connection(s) by removing your tank. It's a one-way trip into Repairsville from that point - you won't be able to re-install the tank as it was.
Step 1: Make sure your gray water tank is empty of all water. It's heavy when full or partially full, and you don't want it to come crashing down on your skull.
Step 2: Download a copy of Airstream's "Interstate Motorhome Parts Book" for your model year (if that link does not work, go to the Library of All Things Airstream start page). Familiarize yourself with your system lay-out, which might look something like this:
|The bottom photo shows a view of the tank removed from the vehicle, angle similar to line drawing but rotated upward.|
Step 4: Disconnect the water level sensor, which in our case was an old-style telephone line plug.
Step 5: Cut the heating pad wire bundle. Shame that this thing had to be hard-wired instead of incorporating a plug, but it can be repaired later.
Step 6: Detach the fitting that connects to the dump valve. Ours was a square-end connector with screws in it.
Step 7: Locate the steel brackets that attach the tank to the chassis. If your Interstate is like ours, they might be showing considerable rust (discussed below). Release each and remove the tank.
Here are a few photos showing our tank and some of the prep work we did on the shield and brackets prior to tackling the challenge of retrofitting the tank itself. The plumbing retrofit and re-installation will come in the next blog post.
|Tank markings, just so you can compare to your own.|
|Close-up of heating pad info.|
|Heat shield, with one of the main tank support brackets visible at upper left of center (square U-shaped metal piece).|
|I see no need to spend extra money on this kind of a mini-job. We do a lot of DIY and have plenty of old paint left hanging around from other projects, so I just used some of whatever we had available.|
|Newly-coated shield exterior.|
|Art shot, close-up of one of the heavily-corroded support brackets. Why would Airstream put its iconic (and resurging) reputation on the line by producing this high-end Interstate, which was a six-figure vehicle when sold in 2007, and then use such crummy quality in some of the parts?? What did they save by using a cheap grade of steel in these support brackets? A buck or two? Penny wise pound foolish because then, a few short years later, someone writes a blog post calling attention to these questionable decisions. I just don't understand that kind of mentality. Do it right the first time so that DIYers don't have to re-do it later!!|
Similar situation with the all-thread down-rods that support the shield. My husband replaced those with stainless steel because the originals had corroded.
|Devotion to DIY, in our case.|