need elp, 1st time thread repair with Heli-Coil

[John McVicker]

Can't figure what I am doing wrong and don't want to buger this up. Trying to repair a striped bolt hole in my lawn mower cly head.

Before I actually drill into the head of a expensive motor I have been practicing on a piece of soft metal. But after inserting the coil I am unable to thread the new bolt.

I've looked at u-tube videos, re-read the instructions and still can't get the bolt in the coil. Hear is what I have done :

1) drilled out the broken bolt.

2) used the suggested size bit that is correct for the size Heli-Coil

3) taped the new hole w/kit supplied tap

4) threaded the coil into this hole, making sure to thread the coil just below the surface. Knocked off the little tang.

At this point I am stumped. The bolt easily threads into the coil before I insert it into my new hole, but not afterwards.

What have I done wrong ?? Thanks for your help

John

 

[Pin_Head]

I have never seen that happen. Sounds like you have the wrong bolt for the helicoil.

 

[John McVicker]

I have never seen that happen. Sounds like you have the wrong bolt for the helicoil.

You are correct sir !

Actually I had the incorrect heli-coil for the bolt.

Moral : Just because the coil threads onto the bolt, this does not mean it's the correct coil.

I was using a m5 coil which seemed to fit the m6 bolt. But when the coil was inserted into the newly drilled m5 hole it naturally compressed & would not accept the m6 bolt. Imagine that !

Thought I was going crazy. Thanks for your response Pin_Head.

John