Contour Enthusiasts Group Archives Forums General Troubleshooting 99% Sure Its My Alternator, Help with other 1%

ITs your alternator. (or wiring associated with alt)



At IDLE your battery should have 14.2-14.6 volts on it.

this is the voltage measured that is being MAD Eby the alternator, not that the battery is ACCEPTING.. (ie, even a BAD battery would have that voltage reading when running, it just simply wouldn't accept the voltage as a charge (due to a bad battery.)

assumes a good battery:
running: 14.2-14.6
off.. 12.0-12.4 (remove surface charge: key off, headlights and interiors on for 60 seconds)

Ray

Ray thanks for the reply

(Here's my thinking:

Swap batteries from my car to his
1. If MY batt in his car is fine, batt is fine, probably my alt.
2. If MY batt in his car is crap still, could be either my batt or alt, but probably which one?

3. If HIS batt in my car is crap volt readings, its my alt.
4. If HIS batt in my car is fine, probably my battery.

Does this seem like a logical process, comments suggestions? )

I left it charging all night (8 hours) and checked it before I left, it was at 13.8. 1 minute later, 13.5. I dont' know if its normal to lose some volts after being charged. I'll check the voltage again in 11 hours or so. IF the volts are back down to 11.5, definite alt?

I'll do that process I described earlier, should find out the problem by tonight. Thanks a lot for everyone's replies, keep em coming.

Normal battery behavior is to show a higher than normal voltage reading after charging until the "surface charge" is bled off. Turn your headlights on for a minute, then measure the voltage at the battery (headlights still on). You should then see 12.6 +/- .2 or .3 volts.

A defective battery with a shorted cell will not allow the charging voltage of 13.8 to 14.4 volts to be measured. It would measure about 1.6 volts lower than expected for each shorted cell.

Just went through this thhis week. Battery with a shorted cell combined with an alternator failure. Spent all day yesterday replacing the alternator on my back on a gravel driveway. No fun..

Your alternator is toast, just quit dicking around and replace it.

Steve

Sho89:

Glad to see your convicted its the alt, today should see that everyone else is as well. As far as the battery, reading my previous post on switching from one car to another, will that accurately to show a bad alt.

Best way to determine bad batt?

I think I'll just buy another battery, don't really want to risk killing a new alt.

Best batt and alt for contour, place to get?

Swiched batt's with my friend who has 1 year old motorcraft battery. His batt in my car was lower than in his with both full load and idle, off. I understand I should keep it in for a week and drive to see better defined results
- But, I put MY battery in his car and volage was normal, saw 14 for the first time.

I convinced its my alt. I will bring both alt and batt to murrays to get tested.

Thanks for the help everyone, let me know if u don't think its alt.

Where should I get a new alt with lifetime warranty for good price?

There are some on ebay for $50 shipped with 6 month warranty, should i just buy a "new" one from autozone or murrays or something?

O'Reilly's (if you have them)- $159 reman with lifetime warranty or $199 new, also with lifetime warranty. Core charge additional. Expensive little bastard!

Steve