Triumph Spitfires are equipped with complex electrical circuits and components that may break down as they age. Although it may seem a daunting task, there are practical steps you can take to solve problems and get your Spitfire operational again.
Lucas Electrics has had a virtual monopoly on supplying electrical systems for British-made automobiles and motorcycles since 1902. The Lucas electrical system is based on isolated grounds that call for two sets of wires for every component. By nature of this design, there are twice as many ground connections with the potential to cause problems in the Spitfire. Resolving any electrical problems begins and ends with a look at the wiring ground connectors.
The battery is the heart of any vehicle electrical system, and it's no different in the Spitfire. Ensuring the battery is fully charged with clean and corrosion-free terminals is fundamental to eliminating electrical problems. Pay particular attention to the area where the ground strap bolts to the chassis. Without a strong and properly charged battery, the rest of the electrical system cannot possibly work well.
Corrosion is the enemy of any electrical system, and Spitfires are particularly prone to faulty connectors. The Spitfire uses male bullet connectors fastened with a metal sleeve that attract corrosion and create havoc with the vehicle's reliability. Checking the security of each connector by gently pulling on it reveals any substandard connectors and corroded wires. Repair any wiring that came loose during the pull testing, and clean all corrosion from both the bullet connector and the sleeve.
According to Spitfire & GT6 Magazine, Spitfire wiring diagrams are notorious for errors due to the hand-built nature of the cars and oversights within the Triumph engineering department. Contacting a local British automobile club can yield a treasure trove of accurate information and experience. Use a logical approach to tracking down a problem; tackle each component one at a time and use a test light to verify the presence or absence of power.