Cruiserdrew
On the way there
There is more than one way to skin a cat, so I thought I would post up my recent dual battery install using the Hellroaring Isolater/Combiner system. I am not an electrical genius and this system is a bit more plug and play than RavenTai's recent excellent write-up. You do have to fabricate your heavy guage wires and need way more cable ends than Hellroaring supplies with the kit. Since the Hellroaring BIC(battery isolater/combiner) operates on a slightly different design philosophy than the Slee circuit design, I'll go into that first, then the install, and then some pictures.
It all started with a call to CDan. I was buying FJ40 parts and happened to ask if he had a 91-92 battery tray. Yep-instock with all the J hooks, bolts and the works-SOLD. With that on the way, I called Slee, got the washer relocation kit sent out and started investigating the options. I like clean installs and having to find and put together solenoids, switches, shotgun shells, circuit boards and the like was not going to get me up and running before the Norcal Wagons Death Valley trip next week. I wish I had Raven's talent for this stuff, but no. My friend Derek Lee (dclee) had installed the Hellroaring BIC on his 80, and I had seen him run his main battery all the way down by running his fridge in Rubicon Springs. To start, he flipped a switch in the cab and we were ready to go. Nice!
So I called Hellroaring and they had made their BIC even better, with the ability to flow even greater amounts of current without heating up, So I ordered the high end model in their line the 95300B. With this system they reccomend you run all your loads off the main battery, since 99% of the time that is sufficient anyway. Then if you do happen to drain it, you ALWAYS have a fully charged battery ready to go. If you ran your fridge off your back up battery, you could be in the position of draining both batteries and having no start options. You can also combine both batteries fully charged to boost winter starter performance, or for winching. THis produces some real advantages when winching since you get less voltage drop and about 3X the performance of a single battery. All of the isolator/combiner functions are controlled from a switch in the cab. The only down side to this, is that your main battery now has to be deep cycle capable, so I also had to buy a huge Optima Marine Dual purpose-Group31. It barely fits in the tray, but has over 1000 CCA for starting and can deep cycle without damage. For those of you concerned about voltage drop-Hellroaring addressed this electronically and both batteries charge at the same full voltage when the truck is running. They state the voltage drop in the unit is less than the voltage drop of the wire from the main battery-less than .001 volt.
So the first step is to move the washer bottle with the excellent Slee kit, and mount the new battery tray-CDan even sent the appropriate OEM bolts that mount the tray to the body-a nice touch. The first real decision is where to mount the BIC. It is about the size of a deck of cards and needs to be protected from shorts. They reccomend vertical mounting to decrease the risk of accidental shorts to ground. That made sense, and I mounted mine on the back of the new battery box in the space between the box and the aircleaner. That is a perfect and well protected space with short wire runs, but you could mount to the firewall as well. I wanted to keep the wire runs as short as possible and the #2 battery has about 1 foot of 4 guage wire to the BIC.
Then from the BIC to the main battery it took about 5 feet of 2 guage cable. For the cables I used Marine spec wire from West Marine. It's expensive but each strand of the copper is tinned and their cable ends are nice tinned brass, so corrosion is not likely. The Marine heat shrink is really excellent, but pricy. I ran the 2 guage wire from the BIC, between the fender and the new battery box, then behind the overflow bottle and into the factory wire race just in front of the radiator. To get there, I had to dissassemble everything in front of the radiator and that took more time than anything else. The 2 guage wire then connects to the main battery-the BIC uses this connection for it's voltage signal and to pass the big currents associated with back up starting or winching. All the wires were sheethed in flexible conduit and tied down to prevent chafing.
To ground the new systen, I used an idea I got here. There is a 10mm threaded boss at the base of the right side of the engine block. The threads are 10 x 1.25mm and I cleaned up the threads and the boss and bolted in my #2 battery ground wire. I fused the ground side of the #2 battery and that protects all of the #2 batterys wiring in the event of a short. There are reasons not to fuse the ground of your main battery, but for a backup it works great.
The next step was the controller. I mounted the switch to the center console tucked out of the way under the dash. The wires pass under and through the dash, then through the firewall grommet on the right side. This makes for short wire runs to the BIC. Everything again got sheethed in conduit and tied down with wire ties to prevent chafing.
You will also notice in the pictures that I converted to all military spec terminals. This makes the job of bolting the big cables together much easier though you do have to modify your fusible links-the wire connectors have a 5/16 hole but the military terminals have a 3/8 bolt-so you have to carefully drill out the center of the connectors. Be careful doing this as I destroyed one set of fusable links. I had a couple of spares (reccomended, only $12 or so) so no big deal.
The Pics are the BIC mounted in place, the remote controller, and the new battery tray with the cabling in place. I will post a few more pics in another post.
edit-I forgot to thank my friends Alvaro Rodriguez and Derek Lee with helping me with the install and especially fishing the controller wires from the cab to the BIC.
It all started with a call to CDan. I was buying FJ40 parts and happened to ask if he had a 91-92 battery tray. Yep-instock with all the J hooks, bolts and the works-SOLD. With that on the way, I called Slee, got the washer relocation kit sent out and started investigating the options. I like clean installs and having to find and put together solenoids, switches, shotgun shells, circuit boards and the like was not going to get me up and running before the Norcal Wagons Death Valley trip next week. I wish I had Raven's talent for this stuff, but no. My friend Derek Lee (dclee) had installed the Hellroaring BIC on his 80, and I had seen him run his main battery all the way down by running his fridge in Rubicon Springs. To start, he flipped a switch in the cab and we were ready to go. Nice!
So I called Hellroaring and they had made their BIC even better, with the ability to flow even greater amounts of current without heating up, So I ordered the high end model in their line the 95300B. With this system they reccomend you run all your loads off the main battery, since 99% of the time that is sufficient anyway. Then if you do happen to drain it, you ALWAYS have a fully charged battery ready to go. If you ran your fridge off your back up battery, you could be in the position of draining both batteries and having no start options. You can also combine both batteries fully charged to boost winter starter performance, or for winching. THis produces some real advantages when winching since you get less voltage drop and about 3X the performance of a single battery. All of the isolator/combiner functions are controlled from a switch in the cab. The only down side to this, is that your main battery now has to be deep cycle capable, so I also had to buy a huge Optima Marine Dual purpose-Group31. It barely fits in the tray, but has over 1000 CCA for starting and can deep cycle without damage. For those of you concerned about voltage drop-Hellroaring addressed this electronically and both batteries charge at the same full voltage when the truck is running. They state the voltage drop in the unit is less than the voltage drop of the wire from the main battery-less than .001 volt.
So the first step is to move the washer bottle with the excellent Slee kit, and mount the new battery tray-CDan even sent the appropriate OEM bolts that mount the tray to the body-a nice touch. The first real decision is where to mount the BIC. It is about the size of a deck of cards and needs to be protected from shorts. They reccomend vertical mounting to decrease the risk of accidental shorts to ground. That made sense, and I mounted mine on the back of the new battery box in the space between the box and the aircleaner. That is a perfect and well protected space with short wire runs, but you could mount to the firewall as well. I wanted to keep the wire runs as short as possible and the #2 battery has about 1 foot of 4 guage wire to the BIC.
Then from the BIC to the main battery it took about 5 feet of 2 guage cable. For the cables I used Marine spec wire from West Marine. It's expensive but each strand of the copper is tinned and their cable ends are nice tinned brass, so corrosion is not likely. The Marine heat shrink is really excellent, but pricy. I ran the 2 guage wire from the BIC, between the fender and the new battery box, then behind the overflow bottle and into the factory wire race just in front of the radiator. To get there, I had to dissassemble everything in front of the radiator and that took more time than anything else. The 2 guage wire then connects to the main battery-the BIC uses this connection for it's voltage signal and to pass the big currents associated with back up starting or winching. All the wires were sheethed in flexible conduit and tied down to prevent chafing.
To ground the new systen, I used an idea I got here. There is a 10mm threaded boss at the base of the right side of the engine block. The threads are 10 x 1.25mm and I cleaned up the threads and the boss and bolted in my #2 battery ground wire. I fused the ground side of the #2 battery and that protects all of the #2 batterys wiring in the event of a short. There are reasons not to fuse the ground of your main battery, but for a backup it works great.
The next step was the controller. I mounted the switch to the center console tucked out of the way under the dash. The wires pass under and through the dash, then through the firewall grommet on the right side. This makes for short wire runs to the BIC. Everything again got sheethed in conduit and tied down with wire ties to prevent chafing.
You will also notice in the pictures that I converted to all military spec terminals. This makes the job of bolting the big cables together much easier though you do have to modify your fusible links-the wire connectors have a 5/16 hole but the military terminals have a 3/8 bolt-so you have to carefully drill out the center of the connectors. Be careful doing this as I destroyed one set of fusable links. I had a couple of spares (reccomended, only $12 or so) so no big deal.
The Pics are the BIC mounted in place, the remote controller, and the new battery tray with the cabling in place. I will post a few more pics in another post.
edit-I forgot to thank my friends Alvaro Rodriguez and Derek Lee with helping me with the install and especially fishing the controller wires from the cab to the BIC.
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