- 98% satisfied customers
- 72h delivery
- 30 dni na zwrot
Description
FINISHED THREADM11 × 1.5
TOLERANCE4H
PRE-DRILLED HOLEØ11.2 mm
LENGTH L189 mm
M11 thread repair tap – STI tap for V-Coil M11x1.5 inserts
Tool dimension table and technical data
| V-COIL M11 THREAD REPAIR TAP | |
|---|---|
| Thread to be repaired | M11 × 1.5 |
| Tolerance class | 4H |
| Tap diameter B | 12.9 mm |
| Overall length L1 | 89 mm |
| Flute length L2 | 29 mm |
| Shank diameter D2 | 9 mm |
| Square drive a | 7.1 mm |
| Pre-drilled hole | Ø11.2 mm |
The V-Coil M11 thread repair tap cuts an STI (Screw Thread Insert) thread for a Helicoil-type insert. The tool restores a load-bearing seat in a stripped hole without increasing the screw size. Once the insert is installed, the hole accepts a standard M11 × 1.5 screw again. The 9 mm shank with a 7.1 mm square drive fits standard hand tap wrenches and square-drive wrenches.
Repairing a stripped M11 thread in steel, stainless steel, cast iron, and aluminum
Materials, tips, and limitations
The tool works in steel, stainless steel, cast iron, and aluminum. Threads strip most frequently in soft metals, while in steel the insert increases the fatigue life of the joint. Typical examples include cylinder head bolt holes in many VW and Audi engines. Keeping the drill perpendicular and installing the insert to its full depth are essential in these applications. The hole for the STI tap is drilled to Ø11.2 mm, at the upper tolerance limit, and tapped with coolant.
The dimensions of the cut STI thread are specified by DIN 8140-2. The M11 thread repair tap has an overall length L1 of 89 mm and a flute length L2 of 29 mm, and is compatible with V-Coil inserts in lengths of 2xD and 2.5xD. A correctly installed insert restores a thread with a load capacity comparable to or greater than the original.
M11 thread repair step by step
From drilling to the nominal thread
Repairing with an insert is faster and less expensive than replacing the entire cylinder head, and the steps below guide you through the complete installation process.
Thread repair M11 with a wire insert
1Drilling
Hole: Ø11.2 mm
2Chamfering the hole entrance
Angle: 90–120°
3STI tapping
With coolant, 4H
4Insert installation
Tang: break off
✓Nominal thread
Screw: M11 × 1.5
In a blind hole, remove the broken-off tang before installing the screw
Helicoil M11 tap (STI) – why it is larger than a standard tap
Compensating for the wire thickness of the thread insert
The STI thread profile remains a metric 60° triangle with a 1.5 mm pitch — only the size changes. The diameter increases by twice the insert wire thickness: D STI = 11 + 1.3 × 1.5 = 12.95 mm. This is why the tool's cutting section measures 12.9 mm, and neither an M12 nor an M14 tap can replace it. Class 4H is the metric equivalent of inch class 3B, also recommended for screw-locking inserts. Once the insert is installed, the bolt engages a standard class 6H thread.
Tap compatibility with the V-Coil insert
What must match before starting the repair
✓Matching size: V-Coil M11 insert with a 1.5 mm pitch.
✓Matching hole: prepare a Ø11.2 mm diameter before tapping.
✓Matching version: available M11 insert lengths: 2xD, 2.5xD.
▲Required inspection: depth and wall thickness of the component being repaired.
This is not a substitute for an M11 tap
The tool cuts only an oversized thread for an insert. A standard M11 bolt will not engage in a hole tapped this way without an insert, and a standard tap will not prepare the hole for an insert.
Frequently asked questions
For the STI thread, drill a hole Ø11.2 mm, rather than 9.5 mm as for a standard M11 thread. Drill at the upper tolerance limit, then chamfer the entrance at 90–120°.
The STI tap cuts a larger profile with a major diameter of approximately 12.95 mm instead of 11 mm, because it accommodates twice the 0.98 mm wire thickness. The 1.5 mm pitch and 60° angle remain the same as on a standard tap. Thanks to DIN 8140, inserts from Helicoil, V-Coil, Recoil, and BaerCoil are interchangeable.
Yes. The inner edge of the wire recreates the nominal M11 × 1.5 thread, so a standard screw can be installed without any modifications. The minor diameter after installation is approximately 9.38 mm, in accordance with ISO 724.
No. M11 × 1.5 is a size used almost exclusively in engines, for cylinder head bolts in many VW and Audi engines, including the 1.8T, 2.0T, and 2.8 V6. It is virtually nonexistent outside automotive applications, which makes the availability of this repair tool important.
Product accessories
M11 2.5xD V-Coil thread repair insert
Reference: 0000013377 In stock < 10 items
€0.82
€1.00 brutto
Reviews
No customer reviews for the moment.
Shipping
All orders are delivered by courier company GLS. For orders exceeding 369 PLN gross shipping is FREE
| Courier GLS | Przelew24 / Prepayment | 14,76 zł gross | Delivery time 1 working day |
| Courier GLS | Cash on delivery | 17,26 zł gross | Lead time 1 working day |
Recommended for you
This website uses its own and third-party cookies to improve our services and show you advertising related to your preferences by analyzing your browsing habits. To give your consent to its use, press the Accept button.
Cookie preferences
Functional cookiesTechnical
Functional cookies are strictly necessary to provide the services of the shop, as well as for its proper functioning, so it is not possible to refuse their use. They allow the user to browse through our website and use the different options or services that exist on it.
Advertising Cookies
These are cookies that collect information about the advertisements shown to users of the website. They can be anonymous, if they only collect information about the advertising spaces shown without identifying the user, or personalised, if they collect personal information about the user of the shop by a third party, for the personalisation of these advertising spaces.
Analytics cookies
Collect information about the user's browsing experience in the shop, usually anonymously, although sometimes they also allow the user to be uniquely and unequivocally identified in order to obtain reports on the user's interests in the products or services offered by the shop.