Hi. I just had to have a helicoil done on one of the spark plugs on my '94 Toy PU. Could anyone tell me if this repair is going to last or should I replace this part of the block? Thanks.

 

If done correctly it will be stronger than the original threads in either cast iron or aluminum. The reason is the outside of the helicoil is a little larger than the original threads so that is stronger. Then the heli coil is stainless steel which is stronger than aluminum or cast iron.

 

Carnut is right. I've been using them for years & not a single failure. Better than new

 

Agree With The Others. Never, Never Had A Failure.

 

I forgot to mention, if you have an aluminum head there are 3 things that can cause stripped threads.
Overtightening, not using anti sieze (on the theads only), and removing the plugs when the engine is hot.
Also never use your ratchet to screw the plug in untill you have screwed it in several turns with your fingers.
Follow these tips & you won't need any more helicoils.

 

Thanks! That's good to know. Taking out the spark plug won't damage the helicoil, though, will it?

 

If the helicoil is installed correctly, you won't hurt it. As mentioned before, put some Anti-sieze on the plug thread, & NEVER service plugs in a hot engine. The Heli-coil will last forever Make sure you torque the plugs to spec when installing new ones because they don't need to be as tight as a lot of people think