Alternator question?

[10thAnnvCobra]

I was driving yesterday in the rain from tropical strom Hannah and the battery light came on and then the ABS light. The wipers slowed and the car wasn't running right, I had to drive "gently". When I got home it wouldn't turn over, no juice. :shrug: I have just hit 70,000 miles and the battery and alternator are original. I assume that the alternator has failed. I will use a meter to test the volts at the battery while it is running with accessories on. I may need an alternator and a battery.

My question... can I test the battery with a voltmeter? I know I can use it to test the alternator. I plan to test it at the battery while running with accessories turned on to create a load. I did a search and it seems that anything under 12.7 volts is bad. If I replace the alternator, which is the best choice? I am leaning towards a new Motorcraft (not remanufactured). Are there better choices? If I have to replace the battery what do you folks suggest? Optima yellow top, red top or just a standard replacement Deka battery from NAPA?

Since my car is a daily driver this is an urgent problem. I need to fix it ASAP. Any comments or suggestions are greatly appreciated.

Thanks - Bob
:beer:

 

[99MustangGTman]

For the alternator, go to modfords and there is a guy that rebuilds them and sells them with all new made in the usa parts, its pretty expensive, but it loos like quality work from what I can tell. As for a battery i'd just go with a standard replacement unless you haver the dough to fork out for an optima. IMO if I were to spend that much money on a battery it would be a lightweight one like n oddssey

 

[32vofFury]

For the alternator, go to modfords and there is a guy that rebuilds them and sells them with all new made in the usa parts, its pretty expensive, but it loos like quality work from what I can tell. As for a battery i'd just go with a standard replacement unless you haver the dough to fork out for an optima. IMO if I were to spend that much money on a battery it would be a lightweight one like n oddssey

or the braille

 

[mixxer]

Replace with stock battery and stock alt.

 

[gcassidy]

Replace with stock battery and stock alt.

+1.

I have an Odyssey that I use in the summer. But I put the stocker back in for the winter. If I was driving all the time (I assume you do if you're driving in a friggin' hurricane), I'd stay with Motorcraft or Diehard.

 

[hook982]

Replace with stock battery and stock alt.

+2:rolling:

 

[10thAnnvCobra]

So far it seems that the stock parts are getting the vote. Most agree with Mixxer. Can I test if my battery is ok with a volt meter? Any other opinions on the battery and alternator?

Thanks for the replies.

 

[01cobravortech]

For the alternator, go to modfords and there is a guy that rebuilds them and sells them with all new made in the usa parts, its pretty expensive, but it loos like quality work from what I can tell. As for a battery i'd just go with a standard replacement unless you haver the dough to fork out for an optima. IMO if I were to spend that much money on a battery it would be a lightweight one like n oddssey

Thats good advice. That dude making those alternators seems to have built a better alternator. I'm waiting for mine too.

 

[Cobrachs]

No you cant test the battery with a volt meter you need a load tester. You can check the voltage but that wont tell you if its failing under load. Unless you have access to a load tester take it to the auto parts store and they will check it for free.

 

[10thAnnvCobra]

No you cant test the battery with a volt meter you need a load tester. You can check the voltage but that wont tell you if its failing under load. Unless you have access to a load tester take it to the auto parts store and they will check it for free.

That's what I thought... thanks for the reply!

 

[Cookieman00x]

jump your car and check your system. You should see about 14.4 volts out of the alternator.. and the same at the battery.. If the car is running and you see that, its the battery. If you take the battery to any advanced autoparts store they will test the battery for free.

However if the car is running and you only see like 12 volts from the alternator, that could be a good indication its the alternator.

 

[Wiseguy]

All good advice. To do this quick get a Alt. from Ford. The remans from Ford have a year warranty also and could save you some. Same day item around here. If you suspect battery being low charge it before you start as you do not want the New Alt to over load its self. Also, average life of a battery is 3-4year depending on conditions.

 

[10thAnnvCobra]

jump your car and check your system. You should see about 14.4 volts out of the alternator.. and the same at the battery.. If the car is running and you see that, its the battery. If you take the battery to any advanced autoparts store they will test the battery for free.

However if the car is running and you only see like 12 volts from the alternator, that could be a good indication its the alternator.

Good information, thanks Kevin.

All good advice. To do this quick get a Alt. from Ford. The remans from Ford have a year warranty also and could save you some. Same day item around here. If you suspect battery being low charge it before you start as you do not want the New Alt to over load its self. Also, average life of a battery is 3-4year depending on conditions.

A new Motorcraft alternator it is. Hopefully I can pick one up on Monday. Good advice about charging the battery before starting. I don't need to toast the new alternator, thanks!

 

[wheelhopper]

More than likely it is just your battery. Older cars can be run with a bad battery once you get it jumped, but todays newer cars completely shut down when the battery goes.

 

[10thAnnvCobra]

More than likely it is just your battery. Older cars can be run with a bad battery once you get it jumped, but todays newer cars completely shut down when the battery goes.

You may be right. The car is just over 5 years old and it still has the original battery. It seems that 3 to 4 years is typical life expectancy, maybe longer if you are lucky... maybe my luck ran out. :shrug: The battery would certainly be easier to replace than the alternator. I'll be doing some testing on Monday and see what I need.

Thanks for the replies. :thumbsup:

 

[10thAnnvCobra]

Has anyone tried this alternator?

DB Electrical

http://www.db-starter-alternator.co...6L 220 AMP HIGH OUTPUT ALTERNATOR 03 04 8304

I assume it will fit a '03 '04 Cobra.

 

[Wiseguy]

Looks good. If the purchase is not local and you have a problem with a new or reman unit and have to send it back- Downtime!!!!

 

[10thAnnvCobra]

Looks good. If the purchase is not local and you have a problem with a new or reman unit and have to send it back- Downtime!!!!

Good point! Plus I would have to wait for delivery. One of the Ford dealers in my area will probably have a new one in stock. I will be checking the alternator on Monday to be sure it needs replacing.

 

[10thAnnvCobra]

Ok, I used my voltmeter this morning. At the battery terminals while idling with no accessories turned on / 12.4 to 12.5 volts. At the battery terminals while idling with all accessories turned on / 11.9 to 12.0 volts.

That seems way low to me and I think the alternator is not putting out. What do you think?

Thanks. :beer:

 

[03CobraDom]

Ok, I used my voltmeter this morning. At the battery terminals while idling with no accessories turned on / 12.4 to 12.5 volts. At the battery terminals while idling with all accessories turned on / 11.9 to 12.0 volts.

That seems way low to me and I think the alternator is not putting out. What do you think?

Thanks. :beer:

Mine went last month..Original Batt/ Alt with 48k... I plugged my X3 in and it was only charging 11.9 volts.. I had a local reputable place rebuild mine for $130

Edit: My original battery is still good tho