On our 2004 Journey 36G, I have installed a positive and negative bus bar to provide an alternative place to attach the 4 positive and 8 negative 12 volt power cables that are connected to the two chassis batteries. Moving the cable connections from the battery posts to the bus bars removed the cable wiring bulk from the top of the two chassis batteries. See the photo below showing the original condition. This installation has allowed easy access to the Interstate 31-MHD battery filler ports for adding distilled water and made it easier to keep the top of the battery clean and the battery studs maintained.
Original Installation
On the Interstate 31-MHD battery the filler ports are normally sealed over with a plastic cover. Interstate battery said that removing the plastic covering allowed access to the filler ports. Maintaining the battery by keeping the correct fluid level will help extend the battery life.
I left the heavy duty 4/0 starting cables connected directly to the batteries. There is too much amperage when starting the engine to do otherwise. I reversed the battery positions 180 degrees in the battery trays so the battery studs are at the back, the filler ports to the front. This arrangement keeps these two large starter cables from interfering with the filler ports.
The bus bars are from Blue Seas. They are rated at 600 amps DC continuous. There are four 3/8" studs. They are designed for marine use so I am confident they will hold up in the Journey's open battery space. There is a cover available to help ward off a tool or whatever that might accidentally be heading to short across the studs. Probably just the positive bus bar needs the cover but I included a cover for the negative bus bar as an aid to help keep it clean.
I looked for a bus bar mounting location close to the batteries. I did some careful measuring and chose the two U shaped channels that support the battery trays. At 3 5/8" there is enough room between the back side of the U channel and the face of the A/C unit for the positive bar and its cover. There is also enough room to torque the nuts down with a box end wrench. The negative bar faces opposite, toward the battery tray and is mounted partially in the space between the U channels. There is 3 " available in this space. Both bus bars are mounted vertically for easier cable connection. Access is attained from underneath the motor home.
Space between bus bar and A/C unit
Bus bars preinstalled to mounting plate
I mounted the bus bars to two steel plates. I purchased a 2" x 24" x 1/8" plate from Lowes. I then cut it to provide two pieces to fit to the out side width of the two U channels: (10 "). I drilled mounting holes for both the bus bars and their covers. I also drilled four mounting holes per plate to attach the plates to the U channels. I decided against using a one piece plate solid because the mounting space is so tight. The open space between the bars allows some visual and finger room. After painting the mounting plate flat black, I pre-mounted the two bus bars to the plates with stainless steel "-20 x 1" bolts with locknuts. As you can see from the photo the bus bars are installed on opposite side of the mounting plates.
Bus bars installed to U channels
With the two chassis batteries removed, I clamped the pre-assembled plates/bus bars to the front of the U channels. Clamping allowed easier control for drilling the mounting holes. I drilled two holes, one in each corner and bolted the assembly tight to the U channels to make sure the other six holes would be accurately located. To mount the plates I used stainless steel "-20 x " bolts with self locking nuts. I had to drill through both sides of the U channel.
After the drilling was complete I removed the assembly from its temporary location and moved it to the backside of the U channels and bolted it in place. The bolts are inserted through the plate and into the back side of the U channel so that the nuts are located in the middle of the U channel. Just made it neater and eliminated the nuts from interfering with anything.
The existing cables that connect the two batteries have a large plate with a connection post. The plate is fastened to the battery stud with a wing nut. There are studs welded to the plate to provide for cable connection. It is a first rate assembly. However, this plate (one at each end of the cable) is so large that it covers a portion of the filler ports. Since I am providing bus bars I only need the battery posts to connect the few remaining cables so I used a simpler connecting cable. I envisioned a 90 degree ring connector. After being told over and over that no such animal existed, I finally found a supplier of an "elbow ring connector." So far I have only found one supplier. I found it at Peterbilt Trucks; they provide a pdf file
here ; the connector can be found on page 61. I purchased the connectors through the local Peterbilt parts dealer. Installation of these new cables allowed me to remove the bulky original connector cable, freeing up filler port access.
Elbow connector ring.
I elected to not shorten any of the existing cabling. In fact, I would not have tackled this project if I had to field mount new ring connectors. I am not saying it couldn't be done, just not a job I am willing to take on.
Experience has taught me not to assume anything about electricity. I had the chassis batteries removed; I did not disconnect the house batteries; nor was shore power plugged in. I put my volt meter across all the positive cables and as I suspected the positive cable that is connected to the stud post adjacent to the chassis batteries had 12 volts. On the Winnebago schematic labeled "Wiring Instl Chassis sheet 2" this isometric drawing shows this stud labeled as "Engine and transmission computer power wires." I just removed this wire from the chassis mounted stud while I was working with it. It was the only "live" cable.
The cable bulk fell quickly apart as I cut the tie wraps. I divided it into negative and positive and organized it. I scooted the creeper under and attached the cables to the bus bars. I used cable hangers (Lowes) with a plastic covered surface over the metal and tie wraps to manage the cable bulk that was now pushed back behind the battery trays. I used the main frame and support steel to tie off the cable hangers. Access to these cables is easy and it just takes some patience and a little pushing and pulling. Because some of the cables had to previously be flexible to move with the battery trays they were not all cable loomed. So I added cable loom where necessary. The cable bulk in its new position is supported and stable.
Negative cables connected to bus bar
Postive cables connected to bus bar
Completed Project (batteries shown in tray rolled out position. Note filler ports in foreground in front of battery studs.
I made sure that movement of both the chassis and house battery trays rolled smoothly with the new cable arrangement. I cranked up the engine and everything purred normally.
The finished product met my expectations and I am pleased with the result.