I changed my spark plugs yesterday. Everything was going smooth. I torqued the plugs in, put the coil packs back, and put the bolts that hold the coil packs back in. I torqued down those bolts as well. Whether or not torquing those bolts is necessary, I did it anyway because it was suggested in the DIY that I followed on here (Saki GT's DIY). I torqued the bolts that hold the coil packs to 8-9 pounds, and the wrench clicked on the first three bolts. Got to the fourth bolt and before the wrench clicked, I noticed it took an extra turn; I thought it was stripped

I kept turning the wrench and the bolt broke, in half.. I was able to get the rest of broken bolt out of the hole where it sits using a magnet. However, I'm getting more and more paranoid because I keep thinking as to how I was able to get that bolt out by just pulling it with a magnet?? I mean, it got screwed in, so why didn't I have to unscrew it to get it out?

Sooo...anyway..it was Sunday and it was past 5:00pm. Only place I could go really was Rural King to try and find a similar bolt to hold that coil pack in. Being 80 miles away from home didn't help how I was feeling after that bolt broke, either. I found a metric bolt that is similar in length and width to the factory bolt; the only difference is that the head is a little different in design. I had the torque wrench set to 8/9 pounds to torque that bolt in, and I started to get nervous because it didn't click either...so I set the wrench to 5 pounds and turned the wrench just slightly and it still didn't click. I was getting way too nervous so I just made sure that the bolt was tight by using my fingers. Decided to just put the coil pack back and go for a test drive. Everything seems fine after driving for 100 or so miles.

I ordered four new bolts from Majestic and will probably be replacing the bolt from Rural King this weekend lol, but I'm just really nervous/paranoid that something is stripped and I'm not even sure if I want to replace it as the bolt I put in seems to be doing its job...I need peace of mind. Thoughts??

 

You definitely stripped the threads on that bolt... There wont be any major problems save for possible misfire due to the coilpack coming loose... Not good for the engine but not fatal. I'd look into alternate methods of securing that coilpack soon.

 

when I had my valvecover powdercoated they didn't protect those bolt holes during the bead blasting phase and they got plastered with beads/sand. I stripped out three holes when I tried to reinstall the bolts as I didn't realize the holes were dirty until I started to wrench on them. It was an easy fix, I just tapped the holes to 7mm x 1mm pitch with a tap, and I got some metric bolts of that size. They work perfectly fine, but the heads are 11mm so I use an 11mm socket on them now. Alternately you could get a helicoil kit for the stock thread size, I believe they are 6mm x 1mm if I'm not mistaken. It is an easy repair to do on soft aluminum like that.

I'd hazard a guess that your torque wrench might be inaccurate on the lower range or those bolts have been over-tightened in the past. The threads on those holes are a bit weak.

 

What size drive is your torque wrench? 3/8" or 1/2"?

I recommend you never you never use a torque wrench on those bolts or any little bolts for that matter. There is too much room for error.

I think a lot of people dont understand what torquing a bolt means. Somehow, "torque them down" is a saying that got adopted, and it implies that bolts need to be "cranked down" as opposed to bolts that you just "snug up".

Bottom line, they are the same thing. ALL bolts must be torqued. Every single one. but that does NOT mean you should use a torque wrench. working on cars over time will give you a feel for how tight to make things. Nothing is a better guide than the right tool. When working with little bolts like that, use 1/4" drive stuff.

I use a torque wrench on lug nuts, oil jet bolts, head bolts, connecting rod bolts, etc. torque wrenchs are needed in these areas becuase more or less torque is critical.

 

3/8"
I should also mention that when that bolt broke, there was just barely enough of the broken bolt sticking out to where I could unscrew it with my fingers. So really I guess i have nothing to worry about.
I will be replacing that bolt this weekend though and have no plans to use a torque wrench on it.

 

So the bolt didn't even bottom out then ?, maybe there is some dirt or crud in the threads of the hole, that will make the bolt stop and it can break in those conditions. You could try to clean it out and run a 6mm x 1mm tap through it to clean up the threads.