The electrolyte level is not checkable that I know of. The battery tested at 64%, or 12.9 volts with the hand held machine autobacs has. I will check the battery tomorrow and see what happens. The battery was purchased in March of '06. The only thing I have noticed is the ticking, which seems to have gone away. There hasn't been a real problem period, aside from the noise.
Bad Alternator signs
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Originally Posted By: Tosh
The voltage continuing to drop from 13.5 to 12.5 after shut-off seems to suggest that the battery isn't holding a charge or that you have large parasitic losses. So don't condemn the alternator just yet.
What's the voltage at the battery after sitting overnight? How's the electrolyte level? How long ago did you get this battery? How long have you noticed a problem? Seems you only suspected a problem when you heard the ticking?
I disagree. That 13.5v is a surface charge and 12.5 is the "real" charge.
One should also observe the temperature when checking batteries; voltage levels described as adequate are at room temperature.
Battery testing instructions almost always say to run the headlights for 5 minutes to kill off a surface charge, a chemical fluke in the battery, to get to the "real" voltage level.
The voltage continuing to drop from 13.5 to 12.5 after shut-off seems to suggest that the battery isn't holding a charge or that you have large parasitic losses. So don't condemn the alternator just yet.
What's the voltage at the battery after sitting overnight? How's the electrolyte level? How long ago did you get this battery? How long have you noticed a problem? Seems you only suspected a problem when you heard the ticking?
I disagree. That 13.5v is a surface charge and 12.5 is the "real" charge.
One should also observe the temperature when checking batteries; voltage levels described as adequate are at room temperature.
Battery testing instructions almost always say to run the headlights for 5 minutes to kill off a surface charge, a chemical fluke in the battery, to get to the "real" voltage level.
Good catch, eljefino! But the alternator is still charging sufficiently, right?
I agree. Maybe it was the ARX rinse oil causing it, I mean, getting to dirty parts for the first time and causing noises.
Mechanic's stethoscope!
Your voltage behaviour seems prefectly normal. In fact some alternators can't even hold 14+ V when idling with load, so that is a good sign the alternator is functioning properly. The gradual drop to 12ish V after shut off is normal also! The battery will always return down to near its native voltage (12v) (usually ~12.6V for healthy batteries) when properly charged shortly after being disconnected from the charger (alternator). Clicking noises are not characteristic of failing alternators.
The voltage regulator is temperature compensated. A hot alternator will put out less than 14V even at 2000RPM.
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