QuestionQUESTION: Hi Dick,
You have come to my rescue in the past, and I hope you will be able to provide assitance again. The battery, which is new, is overcharging in my 64 Bonneville. The reading on the meter is at 17! I replaced the voltage regulator, checked to ensure that it is properly grounded, and it still overcharges (and leaks). The ground straps appear to be grounded. If I remove the leads to the voltage regulator, the readings on the meter obviously drop. Could the alternator need replacement? I don't believe the alternator is the problem since it is, in fact, charging. Any advice or suggestions are greatly appreciated! Oh, also, when I turned on the headlights, and the reading dropped from 17 to 14...I'm not sure if that tells you anything.
Thanks.
Vince
ANSWER: We'll have to do some detective work here.
First, tell me what kind of meter you are using, and exactly where you are connecting it.
Also, measure the voltage between the two battery posts (not on the cable ends, put your test probes right on the round posts of the battery), and measure this voltage before you start the car, then again after the car is running, with no lights on or any other heavy load.
From this information, we can probably track down the problem. For your info, the voltage on the battery posts with the engine running and no lights or other heavy loads should be about 14.4 volts when the battery is fully warmed up, higher if the battery is cold. The voltage on the battery posts when the engine is off, and has been off for at least an hour or so, with nothing at all on in the car, should be about 12.8 or 12.9.
Let me know what you find out and we'll go to step 2!
Dick
---------- FOLLOW-UP ----------
QUESTION: Dick,
My problem has been resolved! About a month ago, I replaced my ignition switch (perhaps you might recall that you helped me with that issue). I decide to inspect my work to see if a mishap on my part might be the culprit in the battery overcharging. Well, I noticed that I did not have the switch properly and securely grounded. Now, my rvoltage readings are acceptable, and there is no more overcharge.
However, can you please tell me if it is possible to measure the voltage post to post (rather than on the cable) since the battery terminals are top monted, and the meter that I have has clamps, not probes.
Thanks, again for ALL of your help!
Vince
AnswerOK, Good, I'm glad you checked that and found the trouble.
You can make a good voltage measurement by any means, as long as you make direct contact between each battery post (or any other point you want to measure) and the metal of the clamps - they don't have to be attached - just touching. You can just hold any part of the meter clamps in contact with the battery post, the meter will read the voltage. You cannot feel the 12 volts - you won't even know you are touching the terminals, (unless your hands are wet, and you are unusually sensitive). If you don't want to do it that way, you can always use a tool such as a screwdriver as a probe, by clamping the meter leads to the metal shank of the screwdriver, and then pushing the screwdriver against the point you want to measure - that way you are only holding the plastic handle of the screwdriver, which is an insulator.
Dick
