Spark Plug High-Voltage Silicone Grease — Ignition Coil Dielectric Compound

Moisture and corrosion at the spark plug boot-to-plug interface cause misfires, hard starts, and premature ignition component failure. A thin application of high-voltage silicone dielectric grease at installation seals the boot against moisture ingress, prevents corona discharge (arcing), and makes future plug removal significantly easier by preventing the rubber boot from bonding to the ceramic insulator.

Technical Specifications

Key Features

• Prevents moisture ingress: Seals the spark plug boot-to-insulator interface against water, condensation, and road splash — eliminates moisture-induced misfires
• Prevents corona discharge: High dielectric strength prevents high-voltage arcing through the boot wall — maintains full ignition energy delivery to the plug gap
• Prevents boot bonding: Silicone barrier prevents the rubber boot from vulcanizing to the ceramic insulator over time — makes future plug removal clean and damage-free
• Extreme temperature stability: Maintains consistency from −50°C cold starts to +200°C sustained engine bay temperatures
• Corrosion inhibitor: Protects metal terminal contacts inside the boot from oxidation in high-humidity environments

Application Instructions

1. Clean the spark plug ceramic insulator and boot interior with a dry cloth
2. Apply a thin, even coat of grease to the inside of the spark plug boot (approximately 0.5 mm thickness)
3. Apply a thin coat to the ceramic insulator of the spark plug
4. Install the plug and press the boot firmly onto the plug until it seats fully
5. Do not apply grease to the plug threads or electrode gap

Frequently Asked Questions

Q: Should I apply this grease to the spark plug threads?
A: No. Apply only to the ceramic insulator and inside the boot. Grease on the threads can affect torque readings and may cause the plug to loosen under thermal cycling.

Q: Is this the same as regular silicone grease?
A: No. This is a dielectric (electrically insulating) silicone compound specifically formulated for high-voltage ignition applications. Standard silicone grease may not have sufficient dielectric strength for ignition coil voltages.

Q: Can I use this on ignition coil-on-plug (COP) boots?
A: Yes. This grease is suitable for both traditional spark plug wire boots and modern coil-on-plug (COP) rubber boots.

Package Contents

• 1× High-voltage silicone dielectric grease (quantity/size as selected)

One application at installation prevents years of moisture-related ignition problems.