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BogusSVO
Well-Known Member
How to install a Heil-Coil
The subject is a Toyota 2ZZ engine block
The bolt holes were cracked and then were welded making the holes out of line. The heil-coil will make this a simple fix.
Original Poster: BogusSVO
Difficulty: 4 out of 10
Time to install: depends on location of stripped hole, avg about 5 mins
Brief Explanation: methoud used for replacing stripped threads in bolt holes
The tools needed will be a Drill motor, the proper sized drill bit for the heil-coil kit, the heil-coil tap, install tool, and the heil-coil insert.
The Heil-coil kit being used is a 8 x1.25mm
The drill bit needed is 21/64
Install the drill bit into the drill motor, and drill the hole out.
Blow out the hole with compressed air
Next take the heil-coil tap
Tap the hole to its oversize.
*NOTE* Heil-Coil taps are an odd size.
On aluminum use a cutting fluid.
Keep the tap straight and square to the work piece.
Blow the hole out again
Now put the insert on the install tool
Now carefully screw the insert into the threads that were just cut, being careful not to apply too much force and skip a thread.
make sure to counter sink the top of the heil coil by a thread or two
Once the insert is in properly, snap the bottom tab off and blow it out of the hole.
All done and ready to have the part bolted back!
The subject is a Toyota 2ZZ engine block
The bolt holes were cracked and then were welded making the holes out of line. The heil-coil will make this a simple fix.
Original Poster: BogusSVO
Difficulty: 4 out of 10
Time to install: depends on location of stripped hole, avg about 5 mins
Brief Explanation: methoud used for replacing stripped threads in bolt holes
The tools needed will be a Drill motor, the proper sized drill bit for the heil-coil kit, the heil-coil tap, install tool, and the heil-coil insert.
The Heil-coil kit being used is a 8 x1.25mm
The drill bit needed is 21/64
Install the drill bit into the drill motor, and drill the hole out.
Blow out the hole with compressed air
Next take the heil-coil tap
Tap the hole to its oversize.
*NOTE* Heil-Coil taps are an odd size.
On aluminum use a cutting fluid.
Keep the tap straight and square to the work piece.
Blow the hole out again
Now put the insert on the install tool
Now carefully screw the insert into the threads that were just cut, being careful not to apply too much force and skip a thread.
make sure to counter sink the top of the heil coil by a thread or two
Once the insert is in properly, snap the bottom tab off and blow it out of the hole.
All done and ready to have the part bolted back!
Last edited:
