12 b7
I have a Gill G-35 in the C182
I took it out and checked the battery voltage. It was down below 4.5 volts.
Aircraft Spruce wants $231 dollars for a new one.
The acid level was a little below the top of the plates.
I added a little water to each cell.
I hooked up the battery charger and very little current flowed. I left it charging
for 18 hours. Voltage is now over 12 volts and charging current is 10 amps.
I was blown away. That battery sat around for years.
I'll learn more when I start the engine with it.
Paul Lamar
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Well I hooked everything up including my 200 amp battery charger. It puts out
200 amp
to aid in starting so it claims. It works on the TTC engine.
In this case the O-470 engine turned over very slowly while the pre oiler was
running. The Gill measured over 12 volts just before I tried to turn the engine
over.
No question of starting.
It could be a lead acid battery that measures the correct voltage
will not put out the current. I don't know of this and never heard
about it.
Looks like I will need to buy a 12 volt battery from Walmart and see how that does.
The prop rotation was so slow I could have turned it by hand.
After this was all over I checked the Gill battery again and it was over 12 Volts. I
am a bit mystified.
Paul Lamar
My Gill did the same thing, showed over 12 volts but failed on delivering any
amps, I
used to have to hand prop the Pacer, once you replace it your worries will go
away. I
also bought an el cheapo cigarette lighter volt/ammeter on Amazon to see how the new
battery does, and it confirmed no voltage regulator issues and normal current draw
for everything except the landing light on my Pacer, so there's a wiring issue on
that circuit that I will fix when I next have time
Alex Molteno
Paul,
I’ve found that my deep cycle trolling motor batteries would only last about two
years.
I also discovered that if I use a small charger called a “Battery Minder” the
interval would increase to about six years. It will usually charge a battery back to
12 V within 24 hours if everything is healthy. At that time it starts blinking
showing that it is using a pulse charge that supposedly destroys the sulfurdatian on
the plates. It was on special for about $39 at Northern Tool? Works great for me.
Barry Bordes
I have frequently seen batteries that will display their appropriate
resting Voltage level, but failed to produce their rated amp hours.
This usually first manifests by slow starting. For 12 V batteries, the
local auto parts place can easily test this function.
I have used the batteryminder device for over 10 years, which seems to
add at least one or two years to the life of aircraft batteries.
Scott Gettings
My inlaw put 30 AH Li-ion battery into his Toyota mini VAN. Weights less than three
pounds. It has build in safety to prevent damage from full discharge.
In my mind much cheaper and safer than a old lead acid battery.
Henry Nee
We had something like that in the TTC for awhile and then it shorted I think.
Little tiny thing. Dan is a electric fan. He has a Tesla.
We were using my 200 amp
battery charger to get it started. That worked for a couple of months.
Then for some strange reason
the engine turned over but it would not start. Turned out the Li-ion shorted and
dragged down the 200 amp charger voltage so the Motec would not work any more.
Kind of opposite to a sulfated lead acid battery.
Took us a couple of weeks to figure that out.
Took out the Li ion and put the lead acid back in.
Now it is starting again.
They are a bit weird and unpredictable :-)
BTW if your battery gets warm when you charge it that is a clue that it is sulfated
and you need the Harbor Freight charger.
Paul Lamar
Paul, and group
Two battery items. First, a lead acid battery will warm any time you charge it. In
good shape it will warm less, but that alone isn't an indication of sulfation. It
can also be an indication that you are charging the battery to fast. Kawasaki
motorcycles devotes some time to battery maintenance in all their technical training
classes. Yuasa sends them the information.
Slower is always better when it comes to charging. The Viking charger Paul mentions
is excellent, as is the "Battery Tender" which is sold at Walmart for about the same
price. Both have a float mode that put a minimum maintance charge on battery while
drawing miliamps. Occasional use machines like planes or motorcycles can be left
hooked up and will always be ready when you want to start them.
Second, beware of the Li-ion battery for aircraft. It is enticing since it is so
much liter and smaller. However recently we had a program at the Livermore CA EAA
chapter 663. Since the chapter is in the shadow of Laurence Livermore Labs they have
a high percentage of highly tech-savvy members. One invited a pioneer in the Li-ion
battery field to do a talk for one of the meetings. His comment, "I would never
run a
Li-ion battery in my own plane."
The reasons are that if the battery ever internally shorts, which is the primary
means of failure in these batteries they will catch fire and release a VERY TOXIC
gas. If you have the resources of Boeing you can build a successful containment so
the plane won't be harmed. In a small scale single battery use you could do it too,
but you would lose all weight advantages you used the battery for in the first
place.
He also commented that this could happen with the battery at rest while minimally
discharging.
The technology has improved enough that it is now fairly rare for one to just fire
up, but it still can and does sometimes happen. If you decide the risk is acceptable
the best thing you can do is to keep the charge above 30% at all times with 30-90%
being ideal. He gave us the quick lodown on the reason the Samsung Note 7's were
catching fire , He said that after reviewing the specs he would have predicted
it. He
also said Apple bought their batteries from one of the best, read safest,
manufacturers although he uses an android phone. All just offered as cautionary
information not as absolutes.
Bill Jepson
An aviation supplier down here in South Africa was selling a Battery Minder
charger/maintainer and I purchased one. However it had a note stating that it
was not
suitable for aircraft batteries. I notice on the Battery Minder website that they do
make an aviation specific one ($240!) and that normal chargers will damage aviation
batteries. They actually have some "technical jargon" as to why. Not being an expert
in the electronics field, does this make sense or is it just a case of "bulldust
baffles brains"?
Pierluigi Ferro
Pier (if I may),
I don't have any idea why the charger wouldn't work. Note that the product I
mentioned is a "BATTERY TENDER" not a battery minder. I don't know if they are the
same product. The Viking from Harbor freight would also be good. I note that there is
a different version of the Viking suggested for Li-ion batteries, but not for AGM or
other versions of lead acid batteries. The arguement sounds like baloney to me. Just
be sure the charger doesn't charge at more than about 2 amps and you should be fine.
Bill Jepson
We have two people that have tested the Harbor Freight Viking on aircraft batteries.
Me and the Kitplanes guy. It worked for both of us.
You are on your own with other brands.
Paul Lamar
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