Undertorquing leads to the plug loosening, which leads to thread damage when combustion pressure stresses the plug.

 

Thanks, I did not know that could happen. I wasn't trying to argue - but I certainly knew there was a danger of stripping threads in aluminum heads by using too much torque.

- Jack

 

Over torquing is rarely a problem. I've seen tests on 4 thread heads where they torqued them to the stripping point and they can go as high as 100 lbs before stripping.

 

Ok, talked to timesert and they told me the kit I needed. It is over $400. So I figured I would see what the ford dealer can do. They told me over the phone that they can do with the head on, and I figured if it was a few hundred more, I would just have them do it. I dropped it off this morning. Just got a call from them, they asked who installed the insert and I told them that I did. They said I that I inserted it too deep, and the only way to get it out is to take the head off. They said this would cost $2500. I'm not sure what to do, or if to believe them. I need my damn truck, but I was thinking of taking it home, and just buy a bore scope at harbor freight to verify this. It is possible that I could have put it in that way, as there was no flange on the insert to prevent this. They there is no internal damage, and these motors are known to go 300k miles. What should I do?

 

Where are you located?

 

Charlotte NC

 

I just called ford and asked the service manager if he could show me with bore scope what they are talking about. He said this was fine, so apparently they are being truthful with me. I guess I am going to have to put out $2500 to get her fixed. More money out of my savings, oh well.

 

The ford dealer installed a bigsert yesterday. They tested it. It seems this cylinder is lower in compression. Looks like I messed something up when I put the first insert in a year ago. I might have screwed it down too deep. I wished that I had found out about the timesert insert before installing the NAPA one. At this point the head needs to come off. Damn! I'm waiting to here from them.