• Drilling - clear the damaged threads with a standard drill. (to repair a spark plug thread no pre-drilling is necessary if using the special spark plug tap), please pay attention that for fluteless taps bigger holes are required.
  • Checking - check that the thread and pitch of the tap and the bolt match.
  • Tapping - use the special taps for cutting the holding thread into the cleared hole (recommended to use a suitable cutting oil).
  • Install the insert - place insert on installation tool and position the adjustable ring so that the insert tang is centered in the tang slot. Wind the insert in with a light downward pressure until a half turn below the surface. Don't work against the thread direction as the tang could break.
  • Tang removal - After finishing lift the installation tool and use the tang break tool to remove the tang. For bigger sizes and spark plug taps use long nose pliers to remove the tang. Due to the narrow and exact tolerances the new thread normally is stronger than the original ones.

Excellent value. I needed to do several inserts and this did the job.

Worked perfect and held tight

This is a very good product!!!!

you will know what to do with it. It comes as a kit with the tools, drill bit, tap, and a good supply of inserts. No instructions, no fancy case, just what you need. I used this to repair stripped threads in an aluminum engine block, and they worked exactly as I hoped. The price to quality was worth the lack of instructions and fancy case.

To quality drill and tap and coils.