PA28 Battery replacement

Hey all. I'm pretty certain I've convinced myself that my "bad starter"
and/or bad ring gear are actually my battery going bad. With the skytec starter, it
makes sense that at high-load, the voltage could drop enough so the starter solenoid
cannot hold the gear engaged to the flywheel. It pops back out while cranking on a
compression stroke.

So, what are the thoughts on the different batteries? I'm pretty sure mine is
the old Gill G35. It's been in there for at least 3.5 years. Any good replacement
ones that might save weight, etc? FWIW it's a 180hp O-360 so it is high compression.

Thanks
-Cory


--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

Cory, we fitted a new Gill 35 sealed battery on our Archer in July 2004.
That battery is now showing signs on a discharge test of being a little
weak.
So I am not convinced about the Gill sealed batteries.

--
Roy
N5804F Piper Archer

"I have had some bad landings but I have never missed the runway"

wrote in message
...
Hey all. I'm pretty certain I've convinced myself that my "bad starter"
and/or bad ring gear are actually my battery going bad. With the skytec
starter, it
makes sense that at high-load, the voltage could drop enough so the
starter solenoid
cannot hold the gear engaged to the flywheel. It pops back out while
cranking on a
compression stroke.

So, what are the thoughts on the different batteries? I'm pretty sure
mine is
the old Gill G35. It's been in there for at least 3.5 years. Any good
replacement
ones that might save weight, etc? FWIW it's a 180hp O-360 so it is high
compression.

Thanks
-Cory


--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

Roy Page wrote:
: Cory, we fitted a new Gill 35 sealed battery on our Archer in July 2004.
: That battery is now showing signs on a discharge test of being a little
: weak.
: So I am not convinced about the Gill sealed batteries.

That was my impression from reading some of the specs. Seems like the SLA
batteries have the plusses of being maintenance-free, but don't last as long.

The one that's in there is the old-school flooded battery.


--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

The consensus at the Cherokee Pilots Chat is that the new sealed
Concord provides maintenance-free service for a reasonable lifetime.
However, the sealed batteries are less forgiving of over-charging, so
make sure that you check that the charging voltage is as specified in
the battery specs.

Some of us P28 owners have been able to fit the XC version into our
battery box - for $20 or so it provides additional cranking power.

Do you have copper battery cables? My Warrior would disengage the gear like
you described until I got the copper cables put in.

Marco Leon


wrote in message
...
Hey all. I'm pretty certain I've convinced myself that my "bad starter"
and/or bad ring gear are actually my battery going bad. With the skytec
starter, it
makes sense that at high-load, the voltage could drop enough so the
starter solenoid
cannot hold the gear engaged to the flywheel. It pops back out while
cranking on a
compression stroke.

So, what are the thoughts on the different batteries? I'm pretty sure
mine is
the old Gill G35. It's been in there for at least 3.5 years. Any good
replacement
ones that might save weight, etc? FWIW it's a 180hp O-360 so it is high
compression.

Thanks
-Cory

Marco Leon mmleon(at)yahoo.com wrote:
: Do you have copper battery cables? My Warrior would disengage the gear like
: you described until I got the copper cables put in.

: Marco Leon

Yes, I've got the copper cables. I've checked the terminals and connections
and they all seem to be in good shape. Looks can be deceiving however, so I'm
planning on going out with an assistant and a voltmeter and track down all the voltage
drops.

With the Skytec starter, I never really had a problem with "cranking power."
It's only the gear disengaging now that's making me suspect. If it turns out it is
the battery and I replace it, I suspect I'll be surprised at how much *extra* cranking
power I'll have. As things slowly degrade you forget what it used to do.

The main reason I'm asking is because another friend of mine put a lightweight
battery in his experimental. I don't know if it's available for certified.

-Cory

--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

wrote:
Hey all. I'm pretty certain I've convinced myself that my "bad starter"
and/or bad ring gear are actually my battery going bad. With the skytec starter, it
makes sense that at high-load, the voltage could drop enough so the starter solenoid
cannot hold the gear engaged to the flywheel. It pops back out while cranking on a
compression stroke.

So, what are the thoughts on the different batteries? I'm pretty sure mine is
the old Gill G35. It's been in there for at least 3.5 years. Any good replacement
ones that might save weight, etc? FWIW it's a 180hp O-360 so it is high compression.

Thanks
-Cory


I took mine to Advanced Auto and had it checked (7 yr old gill). The
battery was fine, I just had to clean the connections. PA32-260

Good Luck!
& sorry bout FS sat.
nxt year?

wrote:
... With the skytec starter, it
makes sense that at high-load, the voltage could drop enough so the starter solenoid
cannot hold the gear engaged to the flywheel. It pops back out while cranking on a
compression stroke.
******************************************

Cory,

Use a good DVM, like a Fluke 75. Use clip leads to connect it between
the stud on the starter and the starter frame. Crank (mixture at
cutoff), and read the voltmeter.

If your voltage drops below 8V, find out why.

Repeat the test with the voltmeter leads connected directly to the
positive and negative poles of the battery. If the battery voltage
drops below about 10V, then replace the battery. If the battery voltage
holds above 10V, then use the voltmeter to do a binary search to find
where the big voltage drop is. Fix that.

Dont overlook that the voltage drop could be across the ground path
between the battery neagive pole and the starter frame.

Personally, I prefer the flooded cell batteries...

: Cory,

: Use a good DVM, like a Fluke 75. Use clip leads to connect it between
: the stud on the starter and the starter frame. Crank (mixture at
: cutoff), and read the voltmeter.

: If your voltage drops below 8V, find out why.

: Repeat the test with the voltmeter leads connected directly to the
: positive and negative poles of the battery. If the battery voltage
: drops below about 10V, then replace the battery. If the battery voltage
: holds above 10V, then use the voltmeter to do a binary search to find
: where the big voltage drop is. Fix that.

: Dont overlook that the voltage drop could be across the ground path
: between the battery neagive pole and the starter frame.

: Personally, I prefer the flooded cell batteries...

Did that this afternoon. It was actually snowing pretty hard here in VA (I'm
outside), so I wasn't too interested in mucking around under the cowling. Put the
DMM's probes *ON* the battery lugs (to eliminate all connections). It read between
9.0-9.35V depending on whether or not it was cranking at a compression stroke or not.
The battery read 12.4V IIRC before I cranked at all, so that'd be about a 75% SOC...
definately good enough to roll over OK.

I have not topped off the battery, but did a 2.5 hour cross country a week ago
and it's been acting up for awhile now. Unless the charging system is broken it's
gotta be the battery. The plane only has a loadmeter, not a voltmeter. Last time I
checked the charging voltage, however, it was fine and the loadmeter's indications
haven't changed since then.

From what I measured, I see about a 1V drop across all the cabling and
solenoids.... probably acceptable for such a long run. I suspect that PA-28's are
extra susceptible to battery strength with such long runs.

-Cory

--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

wrote)
Did that this afternoon. It was actually snowing pretty hard here in VA
(I'm
outside), so I wasn't too interested in mucking around under the cowling.


We just got the word from Virginia that the nieces in Lynchburg will have
'no school' - it's called off because of the snowy forecast. Ages 8 and 10.

Nothing in adult life equals a Snow Day as a kid. g


Montblack