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SKU:
NLT1M01136
Ships for free in 2–4 business days.
Spark Plug Gapping Tool with 32-Blade Feeler Gauge for 10mm 12mm 14mm Plugs
$35.99
In Stock
$35.99
Sale price
$35.99
Regular price
This spark plug gapping set combines an adjustable 10mm, 12mm, and 14mm plug fixture with a 32-blade feeler gauge for measured electrode setup.
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Product Overview
Correct plug gap starts with a real measurement, not a guess or a coin-style gauge that can drag across a fine-wire electrode. This set holds common 10mm, 12mm, and 14mm plugs while the included blade gauge checks the finished gap.
The fixture supports the plug while the ground electrode is adjusted. Fine-wire iridium and platinum center electrodes are delicate and must never be pressed or scraped.
Key Features & Performance
- Threaded fixture supports three common plug sizes
- 32-blade gauge checks actual clearance
- Controlled adjustment is more repeatable than hand prying
Common Uses
- Verifying new plug gap
- Setting a specified gap for a tuned engine
- Checking used plugs during ignition diagnosis
Technical Specifications
- Product Type: Spark plug gapping tool set
- Supported Threads: 10mm / 12mm / 14mm
- Gauge: 32-blade feeler gauge
- Adjustment Target: Ground electrode
- Fitment: Compatible spark plugs
- Use: Measurement and controlled adjustment
Installation & Fitment
- Find the exact gap specification
- Thread the plug gently into the matching fixture
- Measure without forcing the blade
- Adjust only the ground strap
- Recheck gap before installation
Compatibility Notice
Northline Parts does its best to list all known compatible models, but the correct part may fit an application not shown.
Follow the spark-plug manufacturer and engine specification. Some fine-wire, racing, and surface-discharge plugs should not be adjusted.
Frequently Asked Questions
Q: Can it be used on iridium plugs? A: Only if the maker permits adjustment, and the tool must not touch the fine center electrode.
Q: Why use feeler blades? A: Flat blades check a specified clearance without wedging a tapered coin gauge through the electrodes.
Q: Does the tool provide the correct gap? A: No. Obtain the specification from the engine or plug manufacturer.
Q: Will a tighter gap cure a misfire? A: Not by itself; coils, mixture, compression, wiring, and plug condition also require diagnosis.
Part Summary
keywords: spark plug gapping tool, 10mm 12mm 14mm gap fixture, 32 blade feeler gauge, iridium plug adjuster, ignition gap measuring tool
Brand names, model numbers, and reference part numbers are used for identification and compatibility purposes only. Verify the original component, dimensions, and application before purchase.