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C3 Corvette wiring and voltage regulator replacement

Electric Slide: Improve reliability with a new electrical system, lighting and a solid state charging system upgrade for your C3 Vette

Jim Smart Jun 5, 2018
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Few things beat the ambiance and styling of a classic C3 Corvette. These legendary sports cars drew hot attention on Main Street and racetracks 50 years ago and nothing’s changed since. They still excite the senses. The downside to classic Corvettes is the technology we didn’t have in 1968. Mechanical voltage regulators, as one example, can be very problematic, causing inconsistent charging and flickering lights. Old lighting components aren’t much fun either because their function can be hit and miss.

When you’re restoring a C3 Corvette, not only are you confounded at times by dated technology, but also aging wiring, crusty light sockets and poor connections. American Autowire, Corvette Central and Trim Parts can help with everything you’re going to need to get your C3’s electrical system back into solid reliability.

C3 Corvettes from 1968-’71 had fiber optic external light status indication, which alerted the driver to inoperative head, tail, parking and license lamps. Fiber optic cables, which transmit bulb light from external lighting to an indicator panel at the console, have grown yellowed and fogged over time and need to be replaced. American Autowire includes fiber optic cables within its reproduction wiring harnesses, much as they originally were from the factory for easy plug-and-play installation.

Your restoration, be it stock or modified, should include replacement of your Corvette’s electrical system in the interest of safety and durability. Trim Parts sports a huge inventory of lighting options for C3 Corvettes. American Autowire inventories virtually everything you’re going to need to completely rewire your C3 Vette. Corvette Central offers a stealthy solid state voltage regulator you can hide inside of your Delco Remy regulator housing. You can even leave the factory resistors installed if you’re doing a concours restoration and want to keep show judges happy.

We’re at Hot Rods by Dean in Phoenix working with Paul Taylor in our continuing restoration efforts on a ’68 Corvette coupe, which is coming together nicely. Our objective is to restore the car while incorporating hidden modifications that allow us to keep a classic Corvette looking showroom stock while gaining improved driveability and a ride you can take anywhere. Vette

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1. This is the firewall bulkhead connector that ties the main wiring loom behind the dash to the front lighting and engine harnesses. Think of this connector as the nerve center for your classic Corvette’s electrical system.

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2. We’re installing a new American Autowire electrical system to gain reliability we can count on. This is the front lighting harness (PN 05180) and engine harness (PN 01420) from American Autowire, which plug into the firewall bulkhead connection and main wiring harness behind the dash. This connection gets power to the front external lighting, horns, engine, and the rest of it in front. Connections at this juncture should be clean and lubricated to prevent corrosion and keep dirt out.

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3. This is the horn relay, which is a heavy-duty relay switch designed to handle the high-amp draw associated with horn function. When you hit the horn, power from the steering wheel horn switch energizes an electromagnet inside this relay. The electromagnet closes heavy-duty contacts getting power to the horns.

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4. The solid state voltage regulator kit (PN 592024) from Corvette Central replaces your voltage regulator’s original mechanicals inside the regulator housing. It defies detection once the cover is on. You get solid state reliability and lights don’t flicker anymore.

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5. This is the way the Corvette Central solid state voltage regulator looks installed in your existing Delco Remy housing. Install the cover and no one knows it’s there.

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6. Our existing voltage regulator housing will be stripped of its original guts and prepared for the solid state regulator from Corvette Central. You have the option of keeping or removing these resistors. Keep them for a concours-restored appearance.

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7. This is an original Delco Remy mechanical regulator with the cover removed. Back in the day, you could adjust these mechanical voltage regulators. Common failure issue with them is dirty or pitted contact points. Failure issues go away with solid state electronics.

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8. To remove the Delco regulator’s mechanicals, the six rivet heads are ground down as shown for removal. Once the rivet heads are gone, the mechanicals become free.

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9. Here’s the completed solid state regulator conversion. Don’t forget to connect the ground wire to the base.

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10. With the cover installed and the regulator in place, the Corvette Central solid state conversion defies detection and you gain durability and function. American Autowire offers split braid wire wrap you can install on all of your wire looms where you can use more protection. Split braid looks sharp and offers protection against chaffing.

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11. The attention to detail with our American Autowire harness is remarkable. All of the nylon anchor clips are incorporated into the harness per the original.

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12. You get OEM style connectors from American Autowire and the same wire color-coding as your Corvette’s original harness, which makes it easy to do the swap.

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13. The front side marker lights are simple affairs from a time when metal sockets were being replaced by plastic to prevent corrosion. This is an amber (PN 194NA) bulb for one of the front side marker lights.

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14. The front side marker lights from Trim Parts are secured with the speed nuts and bracket from behind. Side marker lights were federally mandated in 1968.

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15. A look behind the fender gives you a better look at how the side marker light is secured. The light socket is inserted and twisted clockwise for easy bulb replacement.

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16. The rear side marker light installs the same way as the front—with a simple insert and twist function. The bulbs are clear (PN 194) and behind a red lens in the rear.

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17. Complete side marker light assemblies are available from Trim Parts, including all mounting hardware. Gaskets are extra for both front and rear side marker lights.

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18. Each front parking lamp includes this fiber optic connection and diffuser, also known as a sensor. Light from the bulb travels through the fiber optic cable wrapped inside the harness to an indicator at the console. When the bulb is lit so is the indicator. When the bulb is out the indicator goes dark.

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19. This is one of two identical front parking lamp assemblies (PN 5801) from Trim Parts. Everything is here including lens and bulb.

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20. These are the parking light harness connectors from American Autowire. On the left is the parking/turn signal light power connection. On the right (arrow) is the fiber optic cable, which connects to the lamp assembly and ultimately at the indicator.

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21. The fiber optic cable connects to the light here at the sensor and grommet. Although called a sensor it is little more than a colored diffuser that helps transfer light to the cable.

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22. Here’s the parking lamp triple-pin connector, which is weathertight.

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23. The installed parking lamp assembly from Trim Parts has been fitted to the grille and is ready for assembly. On the right in this assembly is the fiber optic sensor and grommet.

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24. The front parking lamps get an amber (PN 1157A) bulb, which is appropriate when used with a clear lens.

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25. The parking lamp lens has been installed and secured for a nice, clean installation.

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26. From behind you can see the parking lamp is secured with Tinnerman nuts, which self-tap into the die-cast studs.

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27. The stamped taillight assemblies from Corvette Central sport threaded steel studs instead of die-cast studs like you have in front. Note the fiber optic connector at the bottom.

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28. Here are the taillight harness plugs protruding through the tailpanel. They connect to the taillight assemblies and you’re ready for working lights.

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29. The taillight connector plugs into the lamp assembly as shown, as does the fiber optic cable. The fiber optic cable is for the outboard taillight only.

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30. The taillights have been secured in the body as shown with clear dual-filament (PN 1157) bulbs for parking, brake and turn indicators.

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31. The rear license plate light has power to the bulb to ground (right) and the fiber optic cable (left) for the mid-ship dash indicator.

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32. Here are the two license lamp connectors at the body. On the right is power to the license plate lamp. On the left is the fiber optic cable to the indicator.

Sources

American Autowire
Bellmawr, NJ 08031
800-482-9473
www.americanautowire.com
Hot Rods By Dean
Phoenix, AZ 85027
623-581-1932
www.hotrodsbydean.com
Corvette Central
Sawyer, MI 49125
800-345-4122
www.corvettecentral.com
Trim Parts
513-934-0815
http://www.trimparts.com

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