Hello,
I bought a "sav-a-thread" kit made by helicoil to repair damaged spark plug threads at Napa. However strangely enough this kit uses solid inserts as opposed to the traditional spring helicoil even though it is made by helicoil.
The kit says to use high temp silicone on the threads, presumably to glue the insert down and then a tool is used to expand the insert to help lock it in the hole.
What has the consensus been with these solid spark plug inserts ? Also why did helicoil deviate from their traditional spring product and sell this solid insert instead ?
Thanks,
J