Classic/Antique Car Repair/coil resistor wire

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Expert: - 7/24/2009


Question
I replaced part of the wiring harness on a 72 Corvette. The yellow wire from the starter solenoid to the coil should be a resistor wire. How do I tell if it is or not.I checked the ohms - 2. I also checked other misc. wire in my shop and the ohms is 2 also. I checked the old resistor wire from the old harness,It's 2 also.The old wire has a special sheath around the wire. The new one doesn't.Hope you can help me.  Thanks.

Answer
The wire from the solenoid to the coil should not be a resistor wire. That brings full voltage to the ignition coil for starting when the battery voltage drops because of the heavy load of the starter. The resistor wire should be the one from the ignition switch to the coil. This drops the voltage when the car is running and the alternator is charging. The running voltage to the coil is around 7 volts. The wire from the key to the coil is a ni-cad and changes resistance with heat.
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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