ok so my buddy has a 66 coupe

non- aftermarket wiring......
aftermarget gauges & radio


now what was happening is that his battery gauge was at 10 volts....then later it was 9 volts and tonight (this morning) it was at 8 volts and the car barley wanted to crank over......

he replaced the alternator yesterday.....
he replaced the voltage regulator last week.....
his battery is one of thos red top optima batteries....but it is a few years old....


so tonight around midnight he dropped of his gf....he was driving and the lights went really dim....along with his gauges....the longer he drove...the interior lights gauges and radio.....went complety off....then along with brake lights and his headlights....so he was driving on the freeway heading home at midnight....with not one light....

so alternator is good...brand new less then one day old....
but as long as he didnt turn off the car....the car would keep running

as soon as he got back to his campus....he turned it of.. then tried to re-start and nothing.....

but how can the car run for about 40 mins....with no headlights or any lighting or elec of that matter......

so there could be a few problems...

1. battery is bad.....

2. battery is good......but could it be the oringal wire feeding power to the fuse box off of the solnoid be bad....

3. baterry is good. wire is good. but maybe the solenoid is bad


or what do you guys think it is....he doesn't have a volt meter or else he would check the volts on the battery....so he is going to ask around and try to find that out....but for now lets say the battery is good.....


thanks guys

 

bump [8D]

 

66' s have ammeter gauges not voltmeters. Is this an aftermarket gauge? Regardless, if its not charging, it's the alternator or regulator or wiring. Its also possible that he has a short that's draining the Batt. The quick check for a short is the look for a spark between the battery post and the cable when you touch them together.

Try this quick troubleshooting B4 anything else:

Take the positive cable off of the battery while the car is running and see if it still runs, if it does, the alternator is putting something out and the issue is with the battery. If it dies, the alternator is not working and you'll need to go to autozone, or any of the auto parts stores that will test your charging system in the car. good luck!

 

Your battery isnt getting charged.Ihighly doubtyour battery is bad just because its anOptima, them things can take a beating.But to be on the safe side, you might swap batteries and drive it (in the daytime) and see if it fixes your problem. If it doesnt, itsmost likely your regulator/solenoid.

Before you go spending money, you should clean all your cables and make sure all of your grounds are tight/clean.
Did this occur overnight while parked? Almost sounds like something is draining your battery profusely. Im guessing you added an amplifier/subs since you bought an Optima battery? If so, try disconnecting the amp from the battery and see what happens.

Keep me posted.
-Hawkins

 

As i said in the first post it is aftermarket gauges............

and the car will not try to crank over......


Well he noticed this problem last week, so thats why he replaced the alternator and volt regulator.but the dropping of volts have been droping for the last week....

we are thinking that maybe the wire the feeds the fuse box is bad or maybe the solnoid is bad?[&:] so in that case giving no power to the ignation for a restart or any power inside for that matter or headlights? is that possible?

I have a call into my buddy to try to see if the battery is bad, he doesn't have any tools with him athis college campus. Hopefully he can try to find someone to swap batteries with...... If he does Ill have him disconnect the amp.....and then have him try taking off the positive side of the battery to see if the alternator is working properly......you never have a volt tester when you need one, but you always have one when you dont lol [8D]

I am going to go see him this weekend, and switch out my optima battery with his...if all esle fails, I have a car trialer and we can bring it to his garage to fix it......


EDIT: this 10, 9, 8, volts is when the engine is running at idle.......and he went on to tall me that last week when he had 9 volts and he reved the engine...the volts went back to normal.....but then idle it was still normal and didn't drop.....but that ouccered with the old alternator

 

My best guess is the solenoid. When you get a chance to look at the car ;

1. Clean the batteryposts and the alternator/battery ground. Id even unplug the regulator and plug it back in.
2. While the car is running, disconnect positive feed from battery. Dies - Bad alternator.
3. Turn the car off and swap batteries. Test Drive it w/o the amp feed connected.

If your battery is still being drained, id replace the solenoid beforesearching for a short.

Good Luck!
-Hawkins

 

I just replaced all the wiring in my car as I was having some odd troubles as well, so I feel your pain. Sounds like the solenoid is the last thing to check besides the battery itself. Does the car have a real lopy idle? It is typical for cars to only put out around 9-10 volts during idle, and then around 14 when revving the engine. As far as only getting 8 and lower volts on the voltmeter, that doesn't sound right. I would definitely take the battery out and find a ride to the local Autozone and have the battery checked for free. If you can get the car started, they even check the charging system and battery while it's all still in the car for free. My guess is it's the charging system, not the battery though. It sounds like a pain for sure, but I would just bite the bullet and replace the under hood wiring harnesses. I replaced all the wiring under my hood with brand new reproduction wiring (same color codes, Ford reproductions, direct plug-in replacement) for just over 100 bucks, a couple hours, and some bloody knuckles. In my honest opinion, it beats having to tear into all that electrical tape trying to find a short. It also removes any doubt about the underhood wiring and the possibility of future shorts due to old brittle wiring. +1 on unplugging the amp as well. That's something that can easily get screwed up during installation and cause a short, especially if it's a DIY job. After doing the under hood wiring, and seeing the prices for under dash harnesses, I ended up ripping everything out (including the new stuff) and replacing all the wiring with a new Painless Wiring harness. It's the best thing I've done for my car yet! The difference is incredible! Good luck and keep us posted.

 

hey,

ok so this past weekend we towed his car back to his garage.....it turns out his alternator is bad.

so orginally the alternator thatwas on it, was on itsway out....so he repalced it......and the replacement was completly bad....hahaha...

however he bought it at pep boys and they replaced it without the recepit....

and on the replacement alternator it even had a tag that said passed...... i bet they just put them on all of them lol