Classic/Antique Car Repair/Battery Discharging

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Expert: - 5/23/2010


Question
Car is 1955 Thunderbird.  Battery does not charge while running and is dead overnight.  I have changed the solenoid, voltage regulator and put in a new battery.  How can I find out what is discharging it overnight.  Even when it runs, the gauge shows not charging.   Is it a ground wire somewhere?  Thank you

Answer
My thinking leads me that you need to do a charging system test. That is to check the output of the generator, the setting and operation of the regulator, and a load test of the battery. Once these test are done and they check ok then we suspect a draw in the car that is running the battery dead. The clue here is that you are not showing any charge when the engine is running.
Brad

Classic/Antique Car Repair

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Brad Sears

Expertise

All automotive including antique and collectible. However if the car has been modified I can only answer in general terms and maybe get you pointed in the right direction.

Experience

Automotive tech instructor. Syndicated auto columnist 1970's though the early 1990's. Syndicated auto radio talk show, Ask Brad About cars, CBS Radio 70's through 90's TV Show "Last Chance Garage" 1980's PBS-TV syndicated. Auto instructor for the following companies: Fram Autolyte Holly Carter AMF Ford Motor University Of Conn Blue Hills Technical School Sugar River Technical Center Grew up in a family garage in Needham Mass and turned wrenches from the age of 14.

Publications
Manchester Union Leader, Nashua Telegraph, Motor Service Magazine, Yankee Magazine, Popular Mechanics (Saturday Mechanic early 80's), Los Angeles Times, New York Times, and lots more.

Education/Credentials
More than I care to remember. Basically Franklin Technical Institute in Boston, Northeastern University, Fitchburg State Teachers College, Tufts University, and a lot of factory schools along the way.

Awards and Honors
Moto Award winner. And much more.

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