Last Little Bus Project

Jeff did some research (sometimes known as what would Technomadia do?) and selected the EezTire TPMS system for his rig. Initially, he was planning on the flow-through sensors but we ended up selecting the cap style sensor since they were notably smaller.

He decided that he wanted the system installed using the supplied vaccum mount so that there weren't any new holes added to the dash. The selected position keeps the sightlines to the mirror and the windshield clear.

We had a couple options for power, but wanted to avoid even more cigarette lighter style plugs with cords dangling around. The other option was to used the provided direct wiring cord. I just needed to find a source of keyed power so that the TPMS would be powered only when the ignition key was turned on.

I started at the fuse panel below the dash in the left front corner but bombed out on anything that was easily accessible. Finally found what I was looking for at the back of the radio override switch. This switch had a ground wire, several always hot wires, and one keyed power wire.

I got my work area set up. I discovered there are some advantages to having an inverter. Works great for when you need to power the soldering iron and don't want to start the noise maker. It's worth noting that Mickey D's iced coffee is essential fuel for this project!

I half stripped short sections of the ground and keyed power wires, and then soldered the lead that was provided with the TPMS system.

Some electrical tape on the connections, sliding the conduit back in position, and we were good to go.

The best part was that Jeff arrived just in time to deal with the wire routing behind the dash.

He was also responsible for taking us to the airport a couple hours before he picked up his family and started the first segment of their multi segment roadtrip to Alaska with their motorhome.

Power & Light

Time is running out to get all the projects done on Jeff's Vista, but the list is getting very short as well. One of the projects was to change the stock lights above the bed. The stock puck lights are powered through a single switch and point straight down which isn't very conducive to one person reading while the other tries to sleep. They got re-purposed for lighting in the rear luggage bay.

They were replaced with a couple flexible LED fixtures that we picked up in Quartzsite.

Like nearly all RVs today, the manufacturer seems to assume that you're going to be plugged in or willing to listen to a generator. This rig needed more 12 volt outlets to be functional for dry camping. Dual outlets were placed on each side of the bed pedestal. One outlet has two USB ports while the other outlet accepts a cigarette lighter style plug.

The project was relatively easy since the power converter lives in the same space. It was just a matter of taking the plywood cover off the top of the area behind the converter and the faceplate from the converter, drilling the holes for the outlets, and then running the wires.

I made it a point to run the wire more neatly than the factory wiring. Apparently they figure no one will ever look...

We were fortunately enough to have one empty slot on the 12 volt side, between the blue 15 amp and the brown 5 amp fuses. I picked up the positive feed there and installed a 10 amp fuse.

I was going to run the wire in a plastic conduit but the conduit I brought with me was too small so I used the same technique that the Scamp factory uses to route their wiring - it's tacked in place with hot glue. Both power and ground have a second pigtail soldered into the main lead about 10" back to feed the second outlet. The solder joint is then insulated with shrink tubing - blue because that was what I had in stock.

With these projects done, I think there's just one thing left on the list. I still need to install a power lead behind the instrument panel to power the TPMS system.

Storing Some Juice, II

Our original plan had been to replace the original 12 volt batteries with a pair of Interstate GC2 6 volt golf cart batteries that were easily available from our local Costco, but BJ and I were wandering the Mesa Market Place one day and ran across a couple outfits with excellent prices on Trojan batteries. I turned Jeff loose to do some research. 

He talked with both vendors and ended up getting four US Battery 232 amp hour batteries for $110 each (plus tax.) These were fresh batteries - the construction date stamped on their posts was October 2017. With that sort of pricing, it was an easy decision to upgrade from the 205 amp/hr batteries at Costco.

The original battery tie-down bolts were 9 1/2 inch long carriage bolts. With the new, taller batteries, we needed 11 inch bolts, but my favorite hardware store only stocked them to 10 inch long, so we used Nyloc self locking nuts and fender washer on 12" long piece of all thread. On the top, we were able to reuse the tie plates and nuts. With two batteries in place we were already up about 50% on available amp hours.

The base for the battery box drawer was attached with four bolts through the bottom of the storage bay, retained by fender washers and nyloc nuts on the bottom.

Battery boxes for a pair of GC2 sized batteries are not terribly common. We got this one from All Battery Sales & Service in Everett, Washington because I'd been so happy with the one I've used on our Scamp for the past six years.

I wanted to vent the box overboard so I added a PVC conduit body to the cover, attaching the body with two screws and sealing it with trusty 3M5200.

I'd hoped to be able to vent directly out, but the battery box height was such that the vent would hit the aluminum angle that forms part of the storage bay. I drilled a 2" hole through the back of the bay as well as 7/8" holes for the battery cables.

A couple of elbows and some 1 1/2" PVC pipe created the offset solution for the vent.

The vent pipe slides over the sleeve on the conduit body. The other hole in the conduit body is unnecessary and closed with a plug.

The battery box is retained in the drawer in case the driver wants to try some aerobatics. I elected to us a 4' loop strap from NRS.

The NRS loop strap is built for use on white water rafts, but the cam buckle works excellent and I've had a long history of success with these, so it became my logical choice for a simple tie-down system.

We used 1/0 battery cables from Windy Nation on Amazon for the 18" ones that we needed with the batteries in the original location. Unfortunately, they apparently don't do custom lengths, nor 6' long lengths. I didn't want to deal with the extra length or the wait, so we had cables custom built by a local auto stereo shop for the connections to the batteries in the drawer. They are retained by Adel clamps screwed to some aluminum angle that is riveted in place.

For this system, we're now very battery heavy. The batteries could easily support two or three more panels, but it gives Jeff the capacity to enjoy a week of rainy, overcast fishing without needing to fire up the noise maker.

Storing some Juice

The Vista came stock with a pair of NAPA 12 volt, 75 amp hour rated batteries for the coach circuits. Jeff knew he wanted more power, so we started researching 6 volt golf cart battery options. The plan is to put two in place of the original coach batteries under the stairs and to put the other pair in the bay adjacent to the stairs, alongside the solar controller.

The biggest challenge was making the second pair easily accessible for servicing. We ordered a pair of 250 pound capacity, full extension drawer slides and a battery box for the second pair and then I got busy cutting up some wood.

The plan was to build both the base and the drawer from Baltic birch. I did some dry fitting and drilled for screws to hold the major pieces. 

With the dry fitting completed, I epoxied the seams and screwed the pieces together, expoxied the base, radiused the edges and glassed the structure inside and out. With the weight of the batteries and notorious Alaska roads, we wanted to be sure the base structure would not shift or loosen.

The base was painted and the drawer slides were installed

so that I could start dry fitting the parts for the drawer portion. Amazingly, the vast majority of my initial cuts were correct, with just a couple needing a little additional clearance.

Like the base, the structure was epoxied together

and then glassed inside and out.

Amazingly, everything fit without any shims.

The biggest challenge was the installation of barrel nuts in both sides of the base so that a machine screw could be run through the face of the drawer on both sides. These screws keep the drawer firmly closed in transit. The two screws will be removed when opening the drawer to service the batteries.