The Dual Battery: Part Deux

Over the past month or so, I got increasingly frustrated with the dual battery setup intermittently not providing enough power to the radios. It was weird. The winch would work. But sometimes the radios would power up and sometimes not. Sometimes the inverter would power up and sometimes it would give the low-voltage warning. It got to the point where I started carrying a Fluke Meter just to double-check the battery charge. So I knew a change had to come.

The problem was that it had all been done piecemeal. First the objective was to add the second battery. Then I thought about the inverter. Then I thought about specific loads to add to the second battery. The solar panel came next. Then additional loads and a distribution panel behind the rear bench. There were too many points of failure introduced into the system.

Since I was potentially going to need to undo it all anyway, I started thinking about actually mustering the huevos to fit both batteries under the hood. And so, this became the genesis.

There is one extra long run of #2 cable in here which I have since swapped out. Aside from picking up two additional 20" sections of battery switch cable, I attempted to reuse as much of the suitable wiring that had been retained from the initial iteration of this. It took 2-1/2 days of near steady work. The biggest dilemma I ran into was finding a suitable place for the automatic charging relay and the switch. The Xterra builds after which this was modeled had used different relays and opted to mount their devices above the fuse blocks/panels in the section under the bonnet closest to the passenger right before the firewall. I didn't want to mount anything there which would encumber access to those fuses in the event I needed to swap one out on a trail. It would be bad news if something was suddenly  happening that would result in burning up a fuse; however, it would be something worse if I couldn't readily access it to make a swap with a spare in the interest of keeping moving.

So I spent a lot of time, once I got underway, trying to find an alternate location in a way that would not preclude access to other serviceable areas of the engine bay. I'm not 100% happy with what I ended up doing, but I also didn't think I really  had a viable alternative that would have also allowed me to keep the wiring runs short/consolidated and not blocked fill ports and such. I took a lot of photos; so, I'll walk through what was happening and how I arrived at what, thus far, has proven to be a pretty successful outcome.

 I didn't mean to post this here, but I took a break in the work to drive my wife to her job so I could use her car if I needed parts in a pinch. I just got a kick out of how, this driver, who is also towing a camper, could not find any space in their main vehicle or in the camper to house their razor scooter. It had to be mounted out back, I guess :)

 So this was the sad state of things when I started. When I switched from the stock battery to the first Yellow Top Optima, the posts were too far in towards the midline of the battery compared to the stock battery. The stock harness would not rest on this battery as it had before as the heights were different as well. Well, I came up with this poorly conceived extension and just had that harness zip tied to the power-steering reservoir's tower. Then as I added loads, I used a post extension and another clamp to begin stacking on loads like a bad game of Jenga. It was not good. I was not proud.

When I did the body lift, the reservoir no longer had enough slack to be lifted up and out of its tower. It had to be left out. It also received the zip tie treatment. I was not proud.

 I hated this harness and thought it was a good opportunity to disassemble it.

 You'll need a 10mm socket at times.

 This is some sort of voltage regulator from what I'm told. I needed to remove it from this perch and get rid of the fold in the body panel to make a more flat landing surface for the batteries.

 Up close

 10mm socket undoes all of these bolts.

 Removed the power steering reservoir tower. Two bolts need to be completely undone. The third, because of that C- opening, can be left as is and it'll slide out of the grommet post.

 So I captured all of the PS fluid in a zip lock bag (gallon size) as I disconnected the reservoir. I sat the bag down. The bag was not fully sealed. Despite my efforts, still lost the fluid.

I had some kitty litter left over from disposing of latex paint. (Mix it with paint and allow to dry. Then it can be safely discarded with common trash). Anyway, it became my spill kit.

 Everything unbolted. And filthy. I was not proud of the filth.

 I cleaned up some since I was taking photos.

I was leery of using the angle grinder in such close quarters to cut some of these tabs. At first, I used some pliers and a big hammer to fatigue one tab bending it back and forth and beating it. That got old though. I went ahead and wet down a blanket and stuffed it in the compartment to catch any flying debris.

 Test fitting the batteries just to see if there was truly the space. There was. And not an inch to spare in any direction.

 I thought about mounting the reservoir here. I was worried about the sharp bends needed to make the connections to the hard pipe sections.

 I had the idea to make these battery trays and then have them welded together as like a tiered system. Let me just spoil the plot and say that the endeavor failed miserably. First problem was that my welding setup does not allow me to weld such thin gauge metal as that which I selected. If it does allow for such, then I clearly lack the ability to execute without burning it up. Tried a few approaches of making weld puddles with sacrificial washers to allow them to fuse the angle iron to the sheet metal. It worked, but it was pretty sh*tty to be honest.

The second dilemma was that there is JUST enough clearance for the batteries and their curved contours. The squared portions of these trays could simply  not be accommodated. So I lost a lot of precious time in the acquisition and failed assembly of these trays which are not even used. I'm a little bitter just thinking about it.

 Here was another time suck. I had no business disassembling this harness. I ended up reconnecting all of it. Later in the process, I realized that I could not hope to best this design for its compact handling of the individual fusing of the loads coming off of the harness. Even if I could, the cost of buying suitable replacement fuses (marine grade anyway) was also going to become prohibitively expensive. I came up with a means of mounting this harness securely which will be showcased later.

 Wasted time labeling all of these leads. Dumb.

 I got the idea to use these roof walking pads to build up a flat, shock absorbing base for the batteries.

 This rail became my saving grace. I no longer trusted mounting anything with appreciable weight solely to the firewall. The former liquid tite lead which heads aft to the truck box was mounted with a conduit brace to the fire wall. Off roading and moisture in the bay had allowed the retaining screw to work its way loose.

 I didn't want to rely on mounting the switch and ACR and any other components solely to the fire wall. I had this unistrut laying around. I looked at first traversing the backside of the engine compartment, but I didn't want to block access to the rear fuse box.

I looked at doing something over by the airbox, but I didn't want to block the oil fill port or the AC test ports in that area.

This seemed to be the least obtrusive point to span the compartment.

 I test fit the components here with things literally just laying on top of one another. I also thought of mounting the reservoir towards the end of the run. This at least allowed for a straight shot to both hose inlets/ports.

 When I went to close the hood, the point that interfered was the switch. I notched the unistrut to allow it to sit lower.

 I went through the trouble of drilling these extra holes to mount the mounting plate that was used in the first setup, only to find that the mounting bolt heads were very close to the terminal studs. I was worried about any arcing. Out of frustration, I hastily decided to weld the mounting plate to the unistrut. And in my haste, I welded the plate too close to the unnotched edge. The switch would no longer fit. "You are an idiot, William!"

Very hard on myself.

I was able to notch the edge and allow the switch to seat properly.

 A better view of a cut section of the roof pad. I also was able to use one existing body hole for one hold down, j-hook. The hole at the lower portion of the photo was drilled to accommodate the second hold down j-hook

 Painting the rack.

 I had one battery tray from the rear setup and I bought another for these purposes prior to the sheet metal debacle. I cut the upper one to just fit the dimensions of the primary battery and left the aux battery tray at the stock width but with the length modified as was done with the primary tray.I then attached them both to some metal strapping to unite them and reinforce the assembly.

 At this point, I felt ready to reattach the power steering reservoir.

I got new hoses, but they are not PS hoses by part number. I went to three auto supply stores and none of them sold PS hoses. Pep Boys had kits for power steering, but they also included the hard piping and were meant for direct conversions. They didn't sell hose by the foot. I got reinforced hosing at the stock inner dimensions and have hoped for the best. I ran them long and capped them with orange duct tape.

 I cut off the excess length of the tower, drilled two holes and attempted to bolt it to the rail. In the photo is as far as the reservoir would slide into the bracket. The problem was, that although the void is clear where the screw heads are in the mounted position, the ring around the reservoir could not pass by the obstruction imposed by the screw heads. I went to bed in frustration.

 Although no beer had been consumed up to this point, I thought it was suitable to start the next working day with it. I told friends that I was going outside to do this and would not be going back in until it was done. I was reminded to bring plenty of beer. I had abstained until this point. Now I needed a taste.

 I left the problem children bolted in, fired up the welder and welded this damned thing into place.

That became problematic as well later on. When everything was hooked up, there was a slight kink imposed on the larger of the two hoses. Now I didn't have a good way of sliding the bracket forward or backwards. The hose was bouncing off of the air intake plastic pathway and pushing back towards the reservoir. I was able to do some shifting and finagling of the assembly to clear the kink. This became another time suck. 

 Another time sucking detail had to do with the grounding of the electrical system. The stock grounding wire that connects to the engine was short and not very accommodating. It had a special terminal post bonded onto the wire midway and then the voltage regulator assembly needed to also have the wire lead run through its opening. I had entertained swapping out for another ground wire, but I didn't want to compromise the operation of this assembly. I ended up modifying a bracket from one of the winches into an "L" shape and mounting a portion of the stock tower assembly horizontally where the PS tower used to be anchored. There were threaded nut-serts here that I repurposed for this exercise.

 I then took the battery lead and grounded that at another threaded nutsert. I don't have a picture of it for some reason, but from that grounded spot on the body, I jumped a ground wire over to a terminal post that I affixed to the body adjacent to the coolant reservoir. That is where all of my accessory loads can be grounded as it comes with 4 terminal posts.

This is what the spaghetti looked like before everything was neatly run together, zip tied or shortened to go in their final places. 

It started Friday after work and largely was concluded by 930pm Sunday night.