Decoding the wiring diagram for your classic 1966 Chevelle's big block ignition system can be challenging. This guide will help you understand the intricacies of the system, providing a clear explanation of the wiring and troubleshooting tips. We'll even address some frequently asked questions to ensure you have a complete understanding.
The 1966 Chevelle big block ignition system, while seemingly complex, is actually quite straightforward once you understand the components and their functions. The primary components involved are the ignition coil, distributor, ignition switch, and various other wiring connections. Unfortunately, a single, universally accessible PDF wiring diagram for every 1966 Chevelle big block configuration doesn't exist due to variations in options and accessories. However, this guide will equip you with the knowledge to interpret any diagram you find specific to your vehicle's details (found in your owner's manual or through reputable online resources for classic car enthusiasts).
Understanding the Basic Components
Before diving into the wiring, let's review the crucial components:
- Ignition Coil: This transforms the low voltage from the battery into the high voltage needed to fire the spark plugs.
- Distributor: This distributes the high voltage from the coil to the correct spark plug at the precise moment. It also contains the points (in most 1966 models) or an electronic ignition module (in some later-production models), responsible for triggering the coil.
- Ignition Switch: This controls the power flow to the ignition system, turning it on and off.
- Ballest Resistor (if equipped): This protects the points (if used) from excessive current draw when the ignition is first turned on (reduces voltage to the coil).
How to Find Your Specific Wiring Diagram
The best approach is to locate a wiring diagram specific to your 1966 Chevelle's VIN (Vehicle Identification Number). This number contains crucial information about your car's original specifications. You can find this information in a few ways:
- Owner's Manual: If you have the original owner's manual, it likely contains a wiring diagram section or at least some pertinent information.
- Chevrolet Service Manuals: These manuals, available from classic car parts suppliers or online retailers, provide detailed diagrams and specifications for your specific model year and engine.
- Online Forums and Communities: Classic car forums dedicated to Chevelles are excellent resources. Members often share scanned copies of diagrams or offer assistance in identifying the correct wiring based on your vehicle's information.
Remember to always cross-reference any diagram with your car's actual wiring to ensure accuracy.
Common Problems and Troubleshooting
Many ignition issues stem from simple problems, such as:
- Loose or Corroded Connections: Check all connections for tightness and corrosion. Clean any corrosion with a wire brush and electrical contact cleaner.
- Faulty Ignition Coil: A weak or failing coil will result in a weak spark or no spark at all. Testing is needed to determine the health of your coil.
- Distributor Issues: Problems with the points (if equipped), condenser, rotor, or cap can all lead to ignition problems. These components should be inspected and, if necessary, replaced.
- Ignition Switch Malfunction: A faulty ignition switch will prevent power from reaching the ignition system.
- Ballest Resistor Issues (if equipped): A faulty ballest resistor can cause weak spark or intermittent ignition problems.
Frequently Asked Questions (FAQs)
While we can't address every potential question without knowing the specifics of your car's setup, here are some commonly asked questions about 1966 Chevelle ignition systems:
Q: What's the difference between a points-type ignition and an electronic ignition?
A: Points-type ignitions use mechanical points to trigger the coil, while electronic ignitions use a solid-state module for a more reliable and consistent spark. Electronic ignitions generally provide better performance and require less maintenance.
Q: My car has a very weak spark. What could be causing this?
A: Weak spark can be caused by a number of factors, including a failing ignition coil, worn-out distributor components (points, condenser, rotor, cap), corroded wiring, or a failing ballast resistor.
Q: How can I test my ignition coil?
A: There are several ways to test an ignition coil, often involving an ohmmeter to check the resistance of the primary and secondary windings. Detailed instructions can be found in automotive repair manuals or online resources dedicated to classic car repair.
Q: Where can I find replacement parts for my 1966 Chevelle's ignition system?
A: Many classic car parts suppliers specialize in parts for Chevelles, and parts like ignition coils, distributors, and other components are readily available. Online retailers and local auto parts stores may also carry some items.
This guide provides a foundation for understanding your 1966 Chevelle big block ignition system. Remember to consult your vehicle's specific wiring diagram and utilize reliable resources for accurate troubleshooting and repair. Always prioritize safety when working with electrical systems.
