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SKU:
NLT1M00091
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14mm Back Tap Spark Plug Thread Repair Tool 640811
$23.99
In Stock
$23.99
Sale price
$23.99
Regular price
This 14 mm back-tap thread repair tool works outward through compatible spark-plug holes to chase damaged or carbon-fouled threads and cross-references 640811.
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I reached out for some replacement head bolts and they responded quickly with a few questions and cautionary information and is sending me some bolts. Great customer service! Thanks
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Product Overview
A spark plug that starts crooked, binds before seating, or pulls damaged material from the hole may leave usable threads deeper in the cylinder head. A back tap enters through the opening in a collapsed position, expands below the damaged area, and follows the good threads outward.
This tool is meant for careful thread chasing, not for replacing metal that has been torn away. Confirm the 14 mm thread size and reach before use. Heavy damage, a cracked head, or a hole that will not hold specified plug torque may require an insert or professional machine work.
Key Features & Performance
- Works from the inner good threads toward the outer opening
- 14 mm size for compatible spark-plug holes
- Expandable back-tap design helps follow the existing thread path
- Useful for light cross-threading, carbon, and minor thread deformation
- Cross-references tool number 640811
Common Uses
- Chasing a spark-plug hole with damaged entry threads
- Cleaning carbon and debris from compatible 14 mm threads
- Recovering the original thread path before plug installation
- Evaluating whether threads can be saved before installing an insert
Technical Specifications
- Product Type: Back-tap thread repair tool
- Thread Size: 14 mm
- Application: Compatible spark-plug holes
- Reference Number: 640811
- Quantity: 1 tool
- Condition: New aftermarket service tool
Installation & Fitment
- Verify thread diameter, pitch, access, and cylinder-head construction
- Position the piston and protect the cylinder as the repair procedure requires
- Use suitable cutting grease so debris can be captured
- Expand the tool only in sound threads and work slowly outward
- Remove all debris and confirm the plug threads and torque correctly
Compatibility Notice
This is a universal or service-tool item, not a guaranteed bolt-on part for every vehicle or machine. Measure the available space and compare the dimensions, connections, capacity, operating limits, and intended system before purchase. Custom mounting, adapters, hose, wiring, or professional setup may be required.
Frequently Asked Questions
Q: How is a back tap different from a normal tap? A: It enters collapsed, opens below the damaged entry, and is drawn outward through the existing good threads.
Q: Will it repair completely stripped threads? A: No. Missing or severely damaged threads usually require an insert or cylinder-head repair.
Q: Is this for every spark plug? A: No. Confirm the plug hole uses the compatible 14 mm thread specification.
Q: Is this an original-equipment part? A: No. This is a new aftermarket product. Brand names and part numbers are used only to identify compatible applications.
Part Summary
keywords: 14mm spark plug thread repair tool, 640811 back tap replacement, cross threaded spark plug hole repair, back tap thread chaser, 14 mm cylinder head plug thread tool
Brand names, model numbers, and reference part numbers are used for identification and compatibility purposes only. Verify the original component, specifications, and application before purchase.