Glow Plug : Silicon poisoning

[Steve Smith]

Silicon components in the fuel blend produce a glass-like deposit on the platinum-alloy wire element, causing it to slowly lose its catalytic action. Although the plug element glows brightly and continues to offer reliable startup performance, its temperature rating slowly declines (turns cold), and the engine’s ignition point retards.

When the engine begins to experience idle-performance problems, it’s time to replace the plug. Most reputable fuel manufacturers have stopped using silicon compounds as an anti-foaming agent, but some modelers still give each new litre of fuel a “shot” of Armor.