Battery Replacement and Cold Cranking Amps

I have a Gill G25 battery in my Piper Arrow III (PA28R-201T). I
recently had a situation where I ran out of juice after 4 attempted
starts. While I am sure that I can improve my starting technique (I am
a newbie for this particular plane), I would like to have a bit more
power in my battery, especially in very cold conditions such as we have
up here in central Wisconsin.

An A&P told me recently that I am "stuck" with my G25 battery. He said
that he tested it and that it was "fine."

Based on a recent article in "Aviation Consumer", I learned that the G25
has only about 225 cold cranking amps. I noted that the G35S has 250
cold cranking amps.

(1) Is it true that I am stuck with a G25 battery and that NO OTHER
battery in the world can go in my plane? I find that a little hard to
believe.

(2) If there are other possibilities, can someone recommend one that has
better cold cranking amps that the G25?

Thanks in advance.

-Sami (N2057M, Piper Turbo Arrow III owner)

On 26-Jan-2004, "O. Sami Saydjari" wrote:

I have a Gill G25 battery in my Piper Arrow III (PA28R-201T). I
recently had a situation where I ran out of juice after 4 attempted
starts.

Since you live in central Wisconsin, you know how cold can sap a battery's
charge, particularly if left idle for a few days. But when you say it "ran
out of juice after 4 attempted starts" I am wondering (a) what you mean by
no juice, and (b) what constitutes an "attempt." If you mean that the
battery is discharged to a point where the prop will no longer turn with the
starter, that could mean a lot of things, including a defective starter. If
you mean the battery is completely flat (for example, will not power the
radios), then It could be a problem with your charging system or the leads
to the battery.

Four prolonged start attempts with a very cold engine could easily drain a
very cold battery. How, if at all, do you preheat?


While I am sure that I can improve my starting technique (I am
a newbie for this particular plane), I would like to have a bit more
power in my battery, especially in very cold conditions such as we have
up here in central Wisconsin.

I have an Arrow IV, also with an IO-360. I have found that when the engine
is cold (and "cold" here in the Seattle area is pretty mild by your
standards) it likes a very healthy shot of priming. I leave the mixture
rich and the electric pump on until fuel pressure begins to register (it
takes maybe 7-8 seconds), then pull the mixture back and crank. Then it
usually starts without difficulty. I presume that you have studied the
start procedure shown in the manual. The most critical (and perhaps
counter-intuitive) thing to remember is that the mixture needs to be in full
LEAN (i.e. cutoff) position while cranking. You need to keep your right
hand on the mixture while you turn the key with your left hand so that you
can quickly move the mixture to full rich as soon as the engine begins to
fire.


(1) Is it true that I am stuck with a G25 battery and that NO OTHER
battery in the world can go in my plane? I find that a little hard to
believe.

The battery box in a normally aspirated Arrow is pretty tight -- not much
room for a larger battery. Weight and CG are also considerations.

--
-Elliott Drucker

wrote:


Since you live in central Wisconsin, you know how cold can sap a battery's
charge, particularly if left idle for a few days. But when you say it "ran
out of juice after 4 attempted starts" I am wondering (a) what you mean by
no juice,

I mean that the battery would no longer turn the engine over. The
instruments were still powered.

and (b) what constitutes an "attempt."

An attempt was about 30 seconds of turning the engine over in attempt to
get it to start.

If you mean that the
battery is discharged to a point where the prop will no longer turn with the
starter, that could mean a lot of things, including a defective starter.

Hmmm, how does one determine if the starter is the problem?



Four prolonged start attempts with a very cold engine could easily drain a
very cold battery. How, if at all, do you preheat?

I pre-heated with an external forced air heater under the cowl and a
warming blanket on top of the cowl. This was done for about 2 hours in
advance of the flight.





I presume that you have studied the
start procedure shown in the manual.

Yes, I followed the procedure as descrobed in the POH, including the one
you described.


By the way, thanks so much for taking the time and energy to offer your
good advice here. I am so impressed by just how generous folks are with
their willingness to share their experience and expertise on this forum.

-Sami

On 27-Jan-2004, "O. Sami Saydjari" wrote:

But when you say it "ran out of juice after 4 attempted starts" I am
wondering (a) what you mean
by no juice,

I mean that the battery would no longer turn the engine over. The
instruments were still powered.

and (b) what constitutes an "attempt."

An attempt was about 30 seconds of turning the engine over in attempt to
get it to start.

Well, from what you say your (cold) battery is able to crank the engine for
a total of about 2 minutes before it gets run down. That doesn't sound too
bad to me. You should note, however, that cranking non-stop for 30 seconds
is way too long. You are probably over-heating your starter. Anyway, the
real problem isn't your battery but that your (preheated) engine failed to
start. Properly preheated, it SHOULD start with no difficulty. I would
strongly suspect the impulse gear in the left mag. Or you may be flooding
the engine because of improper start technique (a preheated engine needs
only a little bit of priming) or because of a mechanical problem with the
fuel injection system. After cranking unsuccessfully for a bit, try the
"flooded engine" start technique. (Electric fuel pump OFF, Throttle FULL
OPEN, mixture to IDLE CUT-OFF.)



If you mean that the battery is discharged to a point where the prop
will no longer turn with
the starter, that could mean a lot of things, including a defective
starter.


Hmmm, how does one determine if the starter is the problem?

That doesn't sound like your problem, but a starter would be suspect if it
failed to vigorously crank the engine with a freshly charged battery. Of
course, that problem could be caused by other problems such as loose
electrical connections or corroded battery terminals.


-Elliott Drucker

wrote:
The most critical (and perhaps
counter-intuitive) thing to remember is that the mixture needs to be in full
LEAN (i.e. cutoff) position while cranking. You need to keep your right
hand on the mixture while you turn the key with your left hand so that you
can quickly move the mixture to full rich as soon as the engine begins to
fire.


Over the years, a lot of people have recommended this procedure (mostly
CFIs), but no one has explained to my satisfaction WHY this would work.
Why are you leaning the mixture at exactly the time an extra-rich
mixture is needed? After all, that is why we prime and crank with the
throttle mostly closed. I have come to believe it is one of those old
wives tails that CFIs propagate to make it appear to students that they
are "fixing" a bad start.

Since I have been working on my instrument rating through the fall and
winter, I have been doing a lot more cold weather (well, California
cold) starts than I have in past years. My starts improved immensely after
I started doing one thing: after priming about 150% of my usual
warm-weather cold-start procedure, WAIT for 30-60 sec. before cranking.
This gives the primer fuel time to evaporate in the cylinders and form a
combustible mixture. Works every time, with no pumping of the mixture
control.


Ross Oliver

Ross Oliver wrote:
wrote:

The most critical (and perhaps
counter-intuitive) thing to remember is that the mixture needs to be in full
LEAN (i.e. cutoff) position while cranking. You need to keep your right
hand on the mixture while you turn the key with your left hand so that you
can quickly move the mixture to full rich as soon as the engine begins to
fire.



Over the years, a lot of people have recommended this procedure (mostly
CFIs), but no one has explained to my satisfaction WHY this would work.
Why are you leaning the mixture at exactly the time an extra-rich
mixture is needed? After all, that is why we prime and crank with the
throttle mostly closed. I have come to believe it is one of those old
wives tails that CFIs propagate to make it appear to students that they
are "fixing" a bad start.


Well, (1) it's what my POH says to do, and (2) it seems to work.

Remove SHIRT to reply directly.

Dave

(Ross Oliver) wrote in message ...
Over the years, a lot of people have recommended this procedure (mostly
CFIs), but no one has explained to my satisfaction WHY this would work.
Why are you leaning the mixture at exactly the time an extra-rich
mixture is needed? After all, that is why we prime and crank with the
throttle mostly closed. I have come to believe it is one of those old
wives tails that CFIs propagate to make it appear to students that they
are "fixing" a bad start.

Mainly because if the electric boost pump is running and the mixture
control is in any position other than idle cut-off fuel is being
sprayed into the engine through the injection system.

You want to add slightly more than enuff fuel to get the engine
started, then shut off the flow of fuel (mixure to ICO), it'll lean
slightly when cranking (and after starting, with the mixture back, no
more is being added), reach the proper ratio to start-and-run, then
shove the mixture ahead to add metered fuel to keep it running.

No OWT's-just the operating parameters/limitations of "modern"
continuous-flow fuel injection.

TC

"O. Sami Saydjari" wrote in message ...
I have a Gill G25 battery in my Piper Arrow III (PA28R-201T). I
recently had a situation where I ran out of juice after 4 attempted
starts.

The other thing you may wish to look at is the cable between the
battery and the engine. I believe that a lot of the Cherokee's benefit
from having this replaced.

Of course, your other option is to get an APU cable for your plane.
Used to help the Saratoga in the next tie down start his plane on
cold mornings.

The other thing you may wish to look at is the cable between the
battery and the engine. I believe that a lot of the Cherokee's benefit
from having this replaced.

That is done, but good thought!


Of course, your other option is to get an APU cable for your plane.
Used to help the Saratoga in the next tie down start his plane on
cold mornings.

I was hoping to avoid parasitism

Sami,
You can install a Concorde www.concordebattery.com CB-25, CB-25XC, RG-25
or RG-25XC.
1) Four attempted starts depends on how long you were trying. Most
starters have a 30 second continuous limit.
using that that is 2 full minutes of cranking. That would just about be
the limit for battery capacity.
2) Has your aircraft had the original battery cable (Aluminum in most
models) with the Bogert Copper Cable kit? This improves starting speed
and longevity.
3) Find a more open minded A&P Concorde recently modified the battery
cases so they will fit in the Piper Battery Box.
4) Place your battery on a Charger for an hour a day. Low current. A
standard appliance timer works fine.
5) Use a battery heater.

Michelle (A&P)


O. Sami Saydjari wrote:

I have a Gill G25 battery in my Piper Arrow III (PA28R-201T). I
recently had a situation where I ran out of juice after 4 attempted
starts. While I am sure that I can improve my starting technique (I
am a newbie for this particular plane), I would like to have a bit
more power in my battery, especially in very cold conditions such as
we have up here in central Wisconsin.

An A&P told me recently that I am "stuck" with my G25 battery. He
said that he tested it and that it was "fine."

Based on a recent article in "Aviation Consumer", I learned that the
G25 has only about 225 cold cranking amps. I noted that the G35S has
250 cold cranking amps.

(1) Is it true that I am stuck with a G25 battery and that NO OTHER
battery in the world can go in my plane? I find that a little hard to
believe.

(2) If there are other possibilities, can someone recommend one that
has better cold cranking amps that the G25?

Thanks in advance.

-Sami (N2057M, Piper Turbo Arrow III owner)


--

Michelle P ATP-ASEL, CP-AMEL, and AMT-A&P

"Elisabeth" a Maule M-7-235B (no two are alike)

Volunteer Pilot, Angel Flight Mid-Atlantic

Volunteer Builder, Habitat for Humanity