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Topic: Charging System (Read 5564 times) previous topic - next topic

Charging System

Hey guys,

the voltage gauage on my tbird was reading low, pulled out the multimeter: got like 12V across the battery with the car running. So i figured my 3G alternator died :( went out today to get my alternator tested at advance and it passed. Had the battery tested aswell and they said it just needed recharged. I cleaned up the battery terminals with a wire brush. For the meantime the battery will sit on a charger over night. Anything else worth checking?

Thanks
1986 Ford Thunderchicken, 5.0 AOD w/ Shift kit,  354,XXX miles. 1-Family owned. Original engine+trans.
8.8 Disc Rear w/ 3.73 Posi. CHE Control Arms. '04 Cobra brakes all around. 2000 Cobra R wheels. Tubular front LCA's. MM Steering Shaft. Unlocked Speedo, Lowering springs, Eibach sway bars front and rear. Ram air intake.

Charging System

Reply #1 –
Unbolt and clean all round contacts you can find.
Brian R.
88 2.3t Ranger
83 TC  gt40p motor,Vortech,TFS1 cam,long tubes,MS PnP,T5,8.8,17x9 Cobra 17s

Charging System

Reply #2 –
Did you run a fuse or fuseable link? 12volts at idle sounds like it's just running off the battery. Seconds after a cold start battery voltage will slowly raise from 11.5 up to 12 depending on its overall health and tempetures. Anything below 12.5 the battery is discharging, anything above that and it's getting harged back up. Even a fully dead battery should read around 13v at idle and half charged should easily reach 13.5-14.
My 3g was 13.8 when tested at idle with everything turned on.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Charging System

Reply #3 –
I cleaned the contacts with warm water and a wire brush. Got it all really clean. Yesterday i checked and I have continuity, a couple ohms of resisitance, from the "hot" post of the alternator wiring to the positive lead going to the battery. Got everything tested again today at different shops. Alternator passed again. Battery measured bad at auto zone, nearly bad at advance, and just barely good at sear's. So i think im getting a new battery. The current one is 4 yrs old and just before all this i left the dome light on over the weekend. So i think i killed it :(
1986 Ford Thunderchicken, 5.0 AOD w/ Shift kit,  354,XXX miles. 1-Family owned. Original engine+trans.
8.8 Disc Rear w/ 3.73 Posi. CHE Control Arms. '04 Cobra brakes all around. 2000 Cobra R wheels. Tubular front LCA's. MM Steering Shaft. Unlocked Speedo, Lowering springs, Eibach sway bars front and rear. Ram air intake.

Charging System

Reply #4 –
Anyone got opinions on best batteries????
1986 Ford Thunderchicken, 5.0 AOD w/ Shift kit,  354,XXX miles. 1-Family owned. Original engine+trans.
8.8 Disc Rear w/ 3.73 Posi. CHE Control Arms. '04 Cobra brakes all around. 2000 Cobra R wheels. Tubular front LCA's. MM Steering Shaft. Unlocked Speedo, Lowering springs, Eibach sway bars front and rear. Ram air intake.

Charging System

Reply #5 –
I buy whatever is cheap. I think ive gotten 3-4 years on walmart batteries which are about half the price of parts stores. The parts stores ones usually last 4-5 years for me as long as they arent abused.

Top off the battery overnight and check voltage. Then unhook cables and see where it's at after 24 hours. A drop of more then .2 volts means its junk, especially if it drops below 12 volts. You can also check cranking voltage drop. Anything below about 8 volts usually means a bad battery.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Charging System

Reply #6 –
Optima Red Top, eight years and still going.  Biggest thing with any battery is buying a good charges that will desulfate the battery.  I thought my other Red Top had died so I borrowed my father's AGM battery charger that desulfates and put it on the battery for a couple of days.  Two years later it is still going strong so I am a believer in these chargers and bought one.  Charge my battery with it every so often and zero problems since then.  There are a slew of chargers out there that claim they can do this but the only two I know for sure that can do it are the ones from BatteryMINDer (http://www.batteryminders.com/) and Optima.  You can find the BatteryMINDer brand on Amazon fairly cheap but some will say buying a new battery every three or four years is cheaper.  I would agree up until that battery stranded my ass somewhere.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Charging System

Reply #7 –
interstate battery
 

Charging System

Reply #8 –
yeah, ive looked at both interstate and optima. But ive heard that optimas really need that special charger, whereas for the time being my only charger is a battery tender. so that puts out like 1.5amps. trickle charger
1986 Ford Thunderchicken, 5.0 AOD w/ Shift kit,  354,XXX miles. 1-Family owned. Original engine+trans.
8.8 Disc Rear w/ 3.73 Posi. CHE Control Arms. '04 Cobra brakes all around. 2000 Cobra R wheels. Tubular front LCA's. MM Steering Shaft. Unlocked Speedo, Lowering springs, Eibach sway bars front and rear. Ram air intake.

Charging System

Reply #9 –
The Optima charger are cheap enough and work on non-AGM batteries as well.  It's worth it.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Charging System

Reply #10 –
which optima battery do you run? Part #? cuz the autoparts stores say an optima isnt a direct fit.
1986 Ford Thunderchicken, 5.0 AOD w/ Shift kit,  354,XXX miles. 1-Family owned. Original engine+trans.
8.8 Disc Rear w/ 3.73 Posi. CHE Control Arms. '04 Cobra brakes all around. 2000 Cobra R wheels. Tubular front LCA's. MM Steering Shaft. Unlocked Speedo, Lowering springs, Eibach sway bars front and rear. Ram air intake.

Charging System

Reply #11 –
UPDATE: Put in a brand new optima battery. the voltage gauge still reads low. with the car running i read 11.99 volts across the terminals and with the car off, i read 12.5volts. Any ideas? my alternator has been tested at advance once: passed. and tested at autozone: passed.
1986 Ford Thunderchicken, 5.0 AOD w/ Shift kit,  354,XXX miles. 1-Family owned. Original engine+trans.
8.8 Disc Rear w/ 3.73 Posi. CHE Control Arms. '04 Cobra brakes all around. 2000 Cobra R wheels. Tubular front LCA's. MM Steering Shaft. Unlocked Speedo, Lowering springs, Eibach sway bars front and rear. Ram air intake.

Charging System

Reply #12 –
Is the alternator wired-up as shown in the pic?
With the engine off do you have battery voltage on the alternator B+ output terminal.
If yes, Turn the key on and don't start the engine. Is the alt/Batt warning light on?
If yes, start the engine, does the warning light go off?

Let us know what you see.

Charging System

Reply #13 –
X
Mine is wired like this. I followed an install video from LateModelResto. The heavy duty red wire goes to the postive battery terminal.

So yes, I have voltage at the B+ terminal with the car off.
With the car on, not running, voltage gauge reads low and flashes at me. [full digital cluster]
Starting the engine, voltage gauge still reads low, flashes at me
1986 Ford Thunderchicken, 5.0 AOD w/ Shift kit,  354,XXX miles. 1-Family owned. Original engine+trans.
8.8 Disc Rear w/ 3.73 Posi. CHE Control Arms. '04 Cobra brakes all around. 2000 Cobra R wheels. Tubular front LCA's. MM Steering Shaft. Unlocked Speedo, Lowering springs, Eibach sway bars front and rear. Ram air intake.

Charging System

Reply #14 –
This is the video that I used for reference:
https://www.youtube.com/watch?v=COPftLQiCUY
1986 Ford Thunderchicken, 5.0 AOD w/ Shift kit,  354,XXX miles. 1-Family owned. Original engine+trans.
8.8 Disc Rear w/ 3.73 Posi. CHE Control Arms. '04 Cobra brakes all around. 2000 Cobra R wheels. Tubular front LCA's. MM Steering Shaft. Unlocked Speedo, Lowering springs, Eibach sway bars front and rear. Ram air intake.