Floored, Part 1

It would seem that the hot water tank in my trailer has been leaking for a number of years.

When we got the trailer last year, I noticed a soft spot in the floor near the tank, and while the tank was out at the shop being repaired, I decided to take a closer look. What I found almost made me wish that I hadn't. Ignorance is bliss, after all.

First off, a note about construction. This vintage of RV isn't made of prefabricated panels of exotic materials. It's just wood and tin. It's basically built like a house, only using lighter, cheaper stuff. On one hand, it means it's very vulnerable to rot from water damage. On the other hand, damage can be repaired more easily than more modern RVs, since materials are available at any building supply store.

The floor is built like a layer cake. On top is a layer of linoleum. Under that is a layer of 5/8" plywood. Then a layer of 1x2" lumber, spaced 24" apart, with fiberglass wool insulation in between. Then a layer of cardboard. Then styrofoam, and finally a sheet of aluminum.

What the plywood looked like, under the lino

As I peeled up the lino, I discovered that the water damage had dissolved the glue, and the lino came up easily. Beneath that, the plywood subfloor was still saturated with water. I cut away enough lino to find dry plywood, set a shallow depth on my circular saw, and started cutting.

Since I didn't know how thick the plywood was at this point, it took me two or three tries to get through the floor. I eventually found out that the plywood was 5/8" thick. I also found that the joists were 1x2" lumber, and that they were also pretty rotten. In fact, the ones that weren't rotted black from water damage were dry-rotted. However, it turns out that most of the structural integrity of the floor comes from the plywood itself; the lumber served only as spacers to keep the plywood off the layer of styrofoam.

Beneath the plywood, I found soaking wet insulation.

Under the plywood, between the joists, I found a layer of fiberglass wool insulation. This, of course, had managed to soak up water like a sponge, so I pulled up what I could reach and threw it out. Under the insulation I found a layer of cardboard which was wet with water. Tapping on the cardboard made a sound that made me think that there was a layer of styrofoam underneath, and some measurements indicated to me that there wasn't anything else between that and the layer of aluminum on the bottom of the trailer.

The cardboard beneath the insulation. Also wet.

The cardboard is continuous under the joists; at this point I didn't want to dig any further into the floor. I figured that the styrofoam would be impervious to water anyway, and I didn't want to cut holes in the exterior floor anyway. I dropped a fan in front of the mess to dry it out, and left it for a couple days.

From this I learned a couple important rules about repairing water damage:

1. There's always more rot than you think: You have to be prepared to remove more than you expected. The rot is easily hidden by the waterproof top layer.
2. It's still wet in there: most of the materials that make up a floor absorb water. The longer you've had a leak, the more water will have been soaked up by the materials. And they don't want to let it go. My trailer had been sitting for a couple weeks after I'd stopped the leak and mopped up the visible water, but the wood had soaked up so much, and the lino had trapped it there, that I was still pulling up soaking wet wads of fiberglass and pulpy handfuls of what used to be plywood when I started taking the floor apart.

I also learned an important lesson about water damage. Fix it as soon as possible. Tear it open and dry it out before it starts to rot, or your problems get worse by orders of magnitude.

It looks bad, and at this point I'm faced with two options. One will give me a serviceable trailer, if I'm willing to spend money and do some hard work. On the other hand, Beltane is fast approaching, and that's traditionally celebrated with a big fire. Stay tuned to see what I decided to do.

Getting ready for camping season

We picked up our trailer at a very reasonable price from very reasonable people toward the end of the last camping season. This means we got to use it just enough to really love it, and then it got put away for the winter. Fortunately, I have a nice big carport, which means the trailer was sheltered from the snow. I raised it on blocks to get the tires off the ground, flushed out the water system, brought the batteries in the house, and left it while the cold settled in.

But now, the crocuses are up, and the snow is gone from the roads, which means a new camping season is just around the corner. And that means it's time to get the RV trailer out of hibernation.

There are some tasks that are common to all RVs, like flushing the antifreeze out of the water system, reinstalling the batteries, and giving the running gear a good inspection. However, our trailer is pretty old, so there are some repair issues that need to be taken care of first.

Tires

The trailer tires were pretty bald when I parked it last fall, and they didn't grow any new tread over the winter, much to my disappointment. However, since the trailer was up on blocks, getting the tires replaced was pretty easy.

It's worth noting that, while passenger car tires will fit, there are tires made specifically for trailers, (they have "ST" in the sidewall marking,) and those are what should be used. Trailer tires have a thicker sidewall than car tires, so they can handle more weight and higher operating pressures. This adds up to a stiffer tire. On a car, this would be a bad thing as it would make for a harsh ride, but in a trailer, a soft ride is a problem as it makes the trailer more prone to swaying. ("Trailer sway" refers to that phenomenon where your trailer decides it wants to take you in a new direction. Like the ditch. Or oncoming traffic. At a hundred kilometers per hour.) Here is a video of what it looks like.

Bearings and Brakes

The gentleman that sold me the trailer is a heavy-duty mechanic, so I wasn't expecting any problems with the running gear. That said, he told me he hadn't touched the bearings in five years, so I figured they were due for an inspection. The brakes worked well for the few times I used the trailer last year, but since I would be exposing the brakes in the process of inspecting the bearings, it was a good time to check them out as well.

For each of the wheels, I removed the brake drum/hub assembly, cleaned the grease out of everything, and then inspected the bearings, races, and seals for damage. The bearings and races were in great shape, so I simply packed everything with grease and reassembled the hub. (Here are more detailed instructions.)

As for the brakes, all the magnets were in good shape, and the shoes all had enough lining on them to get through another season. Since this is my first time repacking bearings, I'm probably going to pull the hubs again next spring to see how well I did, and I can decide at that time if I want to replace the brakes or not.

(If you're interested in how electric trailer brakes work, watch this YouTube video.)

It's worth noting that bearings are pretty generic, so you can pick up a spare set, pack them with grease, and throw them in a ziplock bag. If you have a bearing failure on the side of the road, you can get underway with nothing more than some simple tools and about a half-hour of time, instead of having to abandon the trailer to seek help in the next town.

Electrical Upgrade

Being from the early eighties, the coach electrics on this trailer are pretty simple. All the gas-operated appliances have pilot lights, so the electricity is only needed for lights, the water pump, and the blower on the furnace. Electricity is supplied by a 12-volt battery mounted on the trailer tongue, and recharged by an onboard power supply when we're connected to shore power.

Since we bought the trailer, I added a couple power outlets for charging cellular phones and such. I also wanted to relocate the switch for the water pump to a more convenient location. We also do a lot of camping in places where there are no services, so I want to add another battery.

I installed a secondary fuse panel under the front bunk, so that I could put the water pump, light, and power outlets onto separate circuits (so that a short in the power outlet, for example, doesn't kill the water pump.) I also installed a relay near the pump so that I could move the switch further away using thinner wire.

Next, I installed a second battery under the dinette, next to the power distribution panel. It's connected in parallel with the other battery, secured to the floor, and vented to the outside. The venting is necessary since lead-acid batteries produce hydrogen gas when being charged.

Finally, I replaced the plug on the shore power line. The line uses 10 guage conductors, so it's good for 30 amps, but sometime in the past the 30-amp plug had been replaced with a 15-amp one. This was probably done for convenience; it's more common to find a 15-amp outlet than a 30-amp one. Adapters exist to connect this cable to a 30-amp outlet, but I would rather have to deal with the more common situation of plugging a 30-amp plug into a 15-amp outlet. I believe it is safer; if you use an adapter to connect a 30-amp cable to a 15-amp outlet, you know you'll never get more than 15 amps running through your shore power line (since the circuit breaker upstream from the outlet will limit current flow to 15 amps. However, if you use an adapter to connect a 15-amp plug to a 30-amp outlet, you can get 30 amps flowing through your connection. And the 15-amp plug is not designed to handle the extra current. This presents a fire hazard. I'm against fire hazards, so I spent $25 and bought the proper plug and an adapter.