Classic/Antique Car Repair/1989j town car

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Expert: - 12/19/2010


Question
This is embarrassing.  I have a 1989 town car in which I'm attempting to install a new battery.  I say "attempting" because I've forgotten the polarity of the connecting wires.  Does the shorter of the two connect to the negative or positive terminal?

Answer
All US built cars since fifties except the mid fifties Packard use Negative ground. The battery should have marks near the post, + for positive and - for negative.
The positive of the battery is connected to the cable that goes to the starter solenoid while the negative is connected to the cable that runs directly to the engine block. The terminals on the battery are also different diameters. the positive is larger than the negative. As that car has electronics and an alternator hooking the battery up backwards can do some serious damage as well as cause a fire.  

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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