Technology for repairing damaged threads [Toyota Highlander XU20]

Sometimes you may encounter stripping of the internal threads of a nut or bolt hole, usually when the tightening torque is exceeded. Stripping of threads occurs very often, especially when working with aluminum components, since aluminum is so soft that it is very easy to damage the threads.

Typically, only partial shearing of the external or internal thread occurs. After the thread has been calibrated with a tap or die, the thread can continue to work. However, sometimes the thread is significantly damaged. When this happens, there are three options:

1) Drill the hole and tap the thread with the diameter according to the next larger size and use a bolt, screw or stud of larger diameter accordingly.

2) Drill a hole and cut a thread in the hole to install a threaded plug, in which you should drill a hole of the appropriate diameter and cut a thread according to the original size. You can also buy a threaded insert with a pre-cut thread of the appropriate (original) size. In this case, you should simply drill a hole of the prescribed size, and then screw the threaded insert into the hole using a process bolt and lock nut. After the threaded sleeve is completely seated in place, unscrew the bolt together with the lock nut.

3) The third method involves using a proprietary thread repair kit, such as the Heli-Coil or SHmsert. These easy-to-use kits are designed to repair damaged threads in through holes and blind holes. Both kits cover a wide range of thread sizes and types. Drill the hole, tap the threads with the special tap provided, screw in the thread insert, and the threaded hole will match the original diameter and thread pitch. Regardless of the technique you use, work calmly and carefully. Any impatience or carelessness with any of these relatively simple procedures can ruin a day's work and result in major additional costs if you damage an expensive component.