the excellent reputation of the products developed by
Enterprises and available at 4x4rockshop.com,
as well as direct from Kilby and other retailers. Unfortunately,
I had never had quite gotten around to purchasing anything from
them for any of my Jeeps because I traded vehicles so frequently.
So, when I was offered the chance to test an early production
version of his new dual battery tray for TJ’s with air conditioning,
I jumped at it.
Kilby Dual Battery Tray
setups have not been offered for TJ’s with the 4.0L engine
and A/C until now because the return side of the system places
the accumulator right next to the stock battery tray and limits
the room available for two batteries. The Kilby dual battery setup
comes with a new A/C line designed to move the accumulator closer
to the engine and free up that much needed room. You can use this
line or discard it and have an A/C shop fabricate one to suit
your needs if you need a more custom setup. Either way, you will
need to take your Jeep to an A/C shop to have the lines evacuated
and refilled once you replace the A/C line.
The box arrived
from Kilby Enterprises at the shop of Staff Writer, Tony Lopez
in Brighton, Colorado and he and I eagerly tore into it as if
it was Christmas morning! We verified that the parts were all
there and admired the thick, 3/16” black powder coated steel
tray with its milled hold-down bar and KILBY logo. Truly a work
of art and very stout, which considering that each Optima battery
is 43 pounds, it needs to be!
placed a phone call to his friends at Total Car Care, just a few
blocks down the street. Their master A/C technician, Eric Welch,
was intrigued by the idea of seeing a ’03 Rubicon up close,
as well as the Kilby dual battery setup.
Eric examined the new A/C line furnished with
the Kilby kit, hooked up his Robinair service unit, and evacuated
the system in short order. Eric then removed the old line, and
after coating the o-rings with refrigeration oil, installed the
new Kilby line in its place.
that supported the accumulator was flipped over and reattached
to the accumulator and to the firewall. It all fit perfectly.
Eric recharged the system, checked for leaks, and pronounced the
Rubicon fit for summer. The whole operation took 35 minutes and
A/C Lines Before
Kilby line being held in place to show location.
Then it was
back to the shop to install the tray and two new Optima batteries.
Removal of the old battery and tray was accomplished quickly.
Following the instructions, the new tray, with the accumulator
out of the way, went in just as easily.
If you have ever experienced problems with water in the passenger
floorboard when running the A/C during the summer, you know that
the underhood airflow can sometimes force the water back up the
drain hose, which causes the problem. I took this opportunity
to install a ½” plastic elbow into the drain hose.
I filed down the ridges on one end and it slid into the hose easily.
I did this now, because the drain hose will be much harder to
reach with the dual battery tray in place.]
suggested that the PDC (Power Distribution Center) be moved forward
to ease the installation of the batteries. On my Rubicon, the
second battery installed easily enough, so I didn’t move
the PDC. Yours may be different, due to manufacturing variances
at the Jeep factory.
Tray shown installed, after installing the
new A/C line.
Notice that the battery temperature sensor
batteries in position and the hold-down bar in place, all that
remained was to wire the batteries. There are several ways to
wire your dual batteries. Painless Wiring makes a dual battery
wiring harness that includes the option of switching between Battery
A, Battery B, or both. Or, you can choose to use an electronic
isolator from one of several manufacturers which will allow you
to divide your vehicle’s electrical load between the two
batteries, while at the same time, making sure that both are kept
fully charged by the alternator.
Tray with batteries installed.
Tray with batteries installed.
A third option,
which I chose, was to simply wire both batteries together in parallel
– positive to positive, negative to negative. Though you
lose any sort of battery management, this method is the least
expensive, and gives you double the cranking power and double
the reserve capacity. The only absolute requirement is that both
batteries be the same (identical) capacity and age. You cannot
mix and match or the weaker battery will drain the stronger and
could cause both to fail.
I built two new battery cables to link the batteries - each one
about 7 ½” long and 2/0 guage. We soldered the terminals
(use rosin core solder, not acid core) and used heat shrink tubing
to seal the job.
I chose to
reuse the original OEM battery cables and combined them with two
of the new battery terminals supplied with the kit. You’ll
notice from the pictures that I placed the positive cable exactly
where it had been on the original - close to the PDC. The negative
cable was cut loose from the factory loom and placed over next
to the firewall and the accumulator. My thinking, totally unsupported
by any scientific knowledge, was that this positioning would force
the two batteries to act as one, with the current unable to take
a shortcut through just one battery – just as your radiator
hoses are placed at opposite corners of the radiator to avoid
the water failing to flow through the entire radiator.
Completed Installation with wire jumpers
So, how does
it work? Well, after a hard day of winching myself and others,
I had no starting problems and noticed no unusual alternator activity.
Most importantly, I had complete peace of mind that I wouldn’t
be stranded with dead batteries.
there are no other dual battery kits on the market that allow
the use of dual Optima batteries. If these are your battery of
choice, then I would highly recommend the Kilby dual battery setup
for any TJ with A/C and expected heavy electrical loads, such
as lights, stereo, winching, etc.