Houston ,we have a problem!

mthomas58 · 08-22-2007, 07:12 PM

Car left me stranded today in a very bad part of town! (My fault)

Left the office today at 3:00PM to inspect a couple of properties (loan collateral) in a very "dicey" in-town neighborhood.......102 ambient temps and bumper to bumper traffic all the way- a recipe for disaster? OH YEA!

Took 45 minutes to travel my 12 mile distance......heavy traffic.....bus accident......stop lights out, etc. etc, etc. A/C running full tilt (+ 3 spal fans on rear condenser), lights on (not a good idea) and had my front oil cooler override switch on as oil tems were on the rise. Pulled in driveway at my destination (VERY BAD NEIGHBORHOOD) vacant spec home just as my radio went dark (that's not normal!). Turned ignition off. Inspected property quickly then out of there quickly right?.....not so fast!........engine would not turn over!

. Stupid me ....driving a 20 year old car and I did not renew my AAA membership. WHAT THE HELL WAS I THINKING????

Heard the sweet sound of a construction crew around the corner and walked over to see if someone could jump me....crew chief spoke english and was able to get some cables from a worker and jump start me (THANK GOD!)

Left A/C off, lights off, windows down and oil cooler fan off and made a bee line to Advance Auto to have the battery checked - test results: battery good/charge low. Dash warning lights never came on indicating battery charge was low???.

I had very ugly visions of the car being broken into when I got back from the const site or, worse yet, being accosted by several groups of questionable locals that I passed on foot while in the wrong neighborhood wearing a suit and driving a sports car....again, WHAT THE HELL WAS I THINKING??? Scared the crap out of me!

Dodged a bullet today big time!

ischmitz · ischmitz's Garage

Mark, the dash light does not indicate a "low battery" condition. In a working system it illuminates when the alternator draws power from the battery. That is usually the case when the alternator does not turn. (e.g. engine not running, broken fan belt)

Contrary to a generator an alternator needs to get power to its rotor in order to start producing energy. The rotor does not have any field when not powered. Hence with the ignition on but the engine not running the rotor draws power through the alternator light. Once the alternator "produces" energy the regulator controls the voltage fed to the rotor to maintain a certain output voltage and the light goes dark.

In your case you simply had more items drawing energy (fans, radio, lights, ignition) than what the alternator was able to produce at low RPM. This caused the battery to drain slowly.....

Cheers,
Ingo

mthomas58 · 03:06 AM

Quote:

Originally Posted by ischmitz

Mark, the dash light does not indicate a "low battery" condition. In a working system it illuminates when the alternator draws power from the battery. That is usually the case when the alternator does not turn. (e.g. engine not running, broken fan belt)

Contrary to a generator an alternator needs to get power to its rotor in order to start producing energy. The rotor does not have any field when not powered. Hence with the ignition on but the engine not running the rotor draws power through the alternator light. Once the alternator "produces" energy the regulator controls the voltage fed to the rotor to maintain a certain output voltage and the light goes dark.

In your case you simply had more items drawing energy (fans, radio, lights, ignition) than what the alternator was able to produce at low RPM. This caused the battery to drain slowly.....

Cheers,
Ingo

Ingo thanks for the clarification on the warning light function. Would a voltmeter provide an early warning of discharging the battery?

I got the following quote from a website RE a VDO Voltmeter but have learned not to believe everything I read....

"Don't let an electrical problem leave you stranded on the side of the highway, where you might die from thirst, starvation, or an errant cell-phone-talking driver! A voltmeter gauge can give you an early warning of an alternator failure or excessive current draw from a powerful sound system".

If this is true, I may ditch the clock and put the Voltmeter in its place.

charleskieffner · 08-23-2007, 03:38 AM

your choices:

grab can of spray bomb and paint in big letters "ROB ME" and a target on each side of car.............

OR

buy super zoomy mega output alt. from pelican to compensate for all the doodaas that you have running system. i was very leary of adding a pair of hella 550's, pair of h-4's and (4) countem hella rally 4000 compacts in light pod. my upcoming volt gauge will have voltmeter in tach gauge. a little more spendy but one less hole and less wires running down to console.

AND

get local concealed carry weapons permit and carry a kimber/springfield/les baer .45 for when you go into these areas. reality is...........driving a porsche you are a target no matter what. porsche = $$$$$ despite the fact i never carry cash, im still a target no matter what zip code im in good or bad.

.45=life

happiness is a warm .45 snuggled in yer door pocket!

ischmitz · ischmitz's Garage

Mark,

what you really want is an Ampere meter in series with the battery. It measures the current flowing into or out of the battery. It will tell you whether energy is going into the battery (charging) or out of the battery (discharging) at any moment. In addition to that a voltmeter is useful to monitor overall system voltage. If it dropps below 13 volt during normal driving you sort of know something is wrong. If it raises above 15 volts your battery gets cooked because of a broken regulator.

Ingo

frogger · 08-23-2007, 04:08 AM

Mark, what is the condition of your fan/alternator belt? I could be wrong, but I just cannot believe that your battery went completely flat after 45 minutes of use with little charge going back in.

I second Ingo's recommendation for an ammeter. I have a voltmeter but I see the additional benefit that the ammeter provides.

charleskieffner · 08-23-2007, 04:20 AM

remember you were going putt putt through city streets. if car sat for any amount of time you may have amp draw down from clock on radio. running (3) spal fans, a/c, radio, lights etc. is a lot of amps ! going putt putt speeds isnt going to allow alt to charge as if it were going 55 mph continuous down road.

been round and round on vehicles that sit for long periods. mine with alpine stereo will fire w/new optima battery about for a week and 1/2. then battery juice isnt enough to fire. after a week i just throw on 2 amp trickle charger. mines an 87 also. clock drains battery. disconnect battery and then all presets are gone.

choices fer vehicle that sits. optimas hate hi amp charges unless starting hi amps ONLY used for starting car if battery dead. 2 amp charger or disconnect battery. low battery condition usually takes about 45 minutes of run time at 55mph down highway to bring battery up to full charge again.

i live in arizona.............battery hell!

mthomas58 · 08-23-2007, 05:30 AM

Quote:

Originally Posted by frogger

Mark, what is the condition of your fan/alternator belt? I could be wrong, but I just cannot believe that your battery went completely flat after 45 minutes of use with little charge going back in.

I second Ingo's recommendation for an ammeter. I have a voltmeter but I see the additional benefit that the ammeter provides.

(1) I actually stopped by the dealership on the way in this AM to pick up a new alt belt.

(2) My tech happend to walk by so we chatted - he also recommended an Ammeter not a Voltmeter (thanks Ingo)

(3) Had a discussion with a co-worker whose hubby is a cop and gun nut - might look into this further. I've never been in favor of owning a gun but yesterday absolutely scared me!

mthomas58 · 08-23-2007, 05:36 AM

BTW, I was wrong....we hit 104 yesterday here in Atlanta!

I was 4th in line at Advance Auto with battery probs.

ramonesfreak · ramonesfreak's Garage

you would actually use a hand gun to try to stop someone from steeling your car? isnt your life worth more than your car? if your about to be robbed, your actually gonna pull out your .45? I can see using a gun to defend your family if an armed robber was busting into your home...or perhaps if you were camping out in the desert and were confronted by pirates, but pulling a gun out in a "bad" neighborhood...not so smart. get some theft coverage on your insurance policy instead

hbkramer · 08-23-2007, 06:44 AM

You might consider mounting the ammeter (2.5 " dia) on the column ,just left of the speedo. It looks very clean and saves the clock,mine still works.
I will post pics if interested.

mthomas58 · 08-23-2007, 06:50 AM

Quote:

Originally Posted by srandallf

you would actually use a hand gun to try to stop someone from steeling your car? isnt your life worth more than your car? if your about to be robbed, your actually gonna pull out your .45? I can see using a gun to defend your family if an armed robber was busting into your home...or perhaps if you were camping out in the desert and were confronted by pirates, but pulling a gun out in a "bad" neighborhood...not so smart. get some theft coverage on your insurance policy instead

Totally agree with you....my concern is my life and family.

Porsche_monkey · 08-23-2007, 06:54 AM

I think a voltmeter is all you need. Yes an amp-meter is better, it's also a lot more work to instal, and depending on how/where you instal it, it could end up causing problems. A loose connection there and you will have a big problem.

And I'm with scoTT. I'd rather turn my car over and collect the insurance money than use the gun. Once you pull it out you've escalated things somewhat. It's just a car. But then I've never owned, or fired a gun.

mthomas58 · 08-23-2007, 07:07 AM

I don't care about keeping the clock........this might fit nicely in its place

charleskieffner · 08-23-2007, 07:30 AM

well since im 6'3 200 plus i seriously doubt ANY punks unless theres quite a few will wrastle w/me for my car.

see punks do not think like you and i.

they would have to intimidate someone w/a weapon. and that then makes it carjacking.

bang bang bang bang bang bang bang bang..........reload..........repeat! you were in fear of your life or a family members. end of subject! PERIOD!

aint NOBODY TAKING MEIN PORSCHEN or es ist TOT! letter of the law at least in arizona. please read your local carjacking laws!

now if it was (1) mini-me w/bandana and some tats and NO WEAPON.........my behavior may be frowned upon by jury of my peers!