Let’s break this down into a few sections:
Seats · Floor · Walls & Ceiling · Windows
Seats
Before you get started, you really need a blank slate to start from. For most people, the absolute first step in this process is removing the seats.
There are a few schools of thought to this process, and each have their merits. You could simply grab a ratchet and undo the bolts individually. Rust often complicates this. Another idea is using an angle grinder to cut the bolts off, and just removing the seats afterward. I highly recommend testing to see how bad your bolts are before using this approach. If they move without too much effort, it will be more work to use an angle grinder than a ratchet. We went the ratchet route.
I don’t recommend being the person who has to get under the bus and keep the nut from spinning. Lots of rust and dried road grime fell right on us, and days later I was still washing it out of my ears.
Bus seats very slightly depending on the model of bus. In my Bluebird, each seat only had two legs, on the side facing the center aisle. The other side was connected to a chair rail, a little piece of metal sticking out from the wall about 12″ up from the floor. The seats were easy to disconnect from the chair rail, but the legs did give us a few issues. There’s no harm in forcing a stuck bolt – if it breaks, so much the better.
Also worth taking into account when you plan for this part of your project are the under-seat heaters, if your bus has them. They are fairly easy to remove, but a bit heavy, and if you’re not prepared coolant can get everywhere. Trace the coolant lines up towards the engine, and you should find a valve that will close off flow to the under-seat heaters, and will make things a little easier. If you’re planning on a vegetable oil conversion, make sure you take care of and save the coolant lines.
Floor
Great! Now the seats are out and you’re faced with a decision to make. Do you remove the floor, or leave it in place?
Hopefully you’ve thought about this a little bit already. It may depend on your intended use for your bus. If you’re just looking for a cool cheap custom RV you can use on some weekends, the rubber floor may be an asset. If you’re planning on living in your bus, leaving the original floor could cost you headroom and heat retention. We opted to remove the original floor.
This process will also vary slightly depending on the manufacturer of the bus, but in my Bluebird we had a layer of plywood underneath the school bus rubber floor. The plywood had suffered a lot of rot and water damage over time, and was in very rough shape. The damp wood had also caused the metal subfloor to rust, and it was in dire need of attention.
Here you can see the extent of the rust damage. It was in bad shape. To treat the rust, we had two main tools: 1) An angle grinder. 2) Ospho rust treatment. We started by using a knotted wire brush on the angle grinder to remove the surface rust and get down to a cleaner metal surface. We also had to use both cutting and grinding discs to grind down the nails that stuck up from the metal subfloor into the wood, and various other imperfections in the metal. Once much of the surface rust was removed, we applied a generous coat of Ospho rust treatment. The gist of this is that it turns Iron Oxide (rust) into Iron Phosphate, which doesn’t spread and destroy adjacent metal. The iron phosphate can be brushed off and removed, leaving a significantly cleaner looking floor.
This is a great improvement, but once we’ve done all this work we want to make sure it stays nice for some time to come. We want to paint on a rust inhibitor. If you have the money, a product called POR-15 is pretty spectacular. If you don’t, Rustoleum also works pretty well. We used Rustoleum Rusty Metal Primer.
Walls & Ceiling
Again, removing the walls and ceiling isn’t for everyone, but if you’re on the fence, I’d say to do it. When your project is done, you won’t be looking back regretting the extra work you didn’t have to do, you’ll regret the work you skipped. The insulation in your walls and ceiling are likely in rough shape. Much of the batting in my walls had water damage, and one panel even had a mouse nest!
You don’t know what’s waiting for you behind those wall panels, and it’s best to not be surprised by these kinds of things.
I may be beating a dead horse here, but this section will vary wildly depending on bus manufacturer. The walls and ceiling of my Bluebird are riveted in place. Other manufacturers use screws. Screws are obviously preferable when you’re in demolition mode.
The easiest way we found to deal with rivets was to cut an X in the head with an angle grinder, then hit the head off with a chisel.
You can also try drilling out the rivets, but we found this to be slower than using an angle grinder. I’m told by other people that you can accomplish this with a chisel alone, but apparently I just don’t have the strength for that. If you have one, an air chisel would be really helpful here.
We didn’t have an air chisel. There are definitely better ways of doing this, and this seems like a good place to mention that I don’t know everything, and I’m just sharing my experiences as an unskilled bus converter.
Note that only the top part of the walls are coming off. The chair rail I talked about earlier is actually more structural than the rest of the walls and ceiling. It runs under the ribs of the bus, below the metal floor. It is not possible to completely remove this.
This did not deter us, and with the help of our faithful friend, the angle grinder, we had cut out openings in our walls.
I honestly cannot say whether or not this is a good idea. I’m sure it weakens the walls structurally, but I can say it doesn’t weaken them to the point of causing even the slightest problem in regular use.
Approach the ceiling the same way you did with the walls. X through the rivets, and then chisel off the heads. Take extra care when working above your head.
Also, remember that ceiling panels will reach a tipping point when you begin to chisel the rivet heads off, where the panels and insulation above them will fall right onto your head.
Take a look at how the panels are assembled. In our bus we worked from the back to the front, since that’s how the panels were layered.
Windows
Only a short word here on windows. I chose to keep all of the original windows in my bus, but if you’re looking to replace or skin over any, now is the time to do it. There are lots of folks who have done this very well, and I’ll leave it to them to give you advice on how best to approach it.
If you do want to keep the stock windows, I cannot emphasize enough that you should re-seal them, and do a pretty thorough leak test while the walls and ceiling are down. This is your big chance to keep air and water from coming right through your windows into your fort – don’t miss it!