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I was making the initial pass of 15ft/lbs and the bolt broke off but the torque wrench never clicked! It's the first time I've used the torque wrench in a while and I'm wondering if maybe it was not working and I over-tightened the bolt?
I believe its safe to say my engine is ruined. I can't imagine how I can extract a bolt so deeply embedded in the block or thread another bolt into the broken bolt. I think its fate telling me to dump this never ending repair job on a beautiful car.
Step 1. grab adult beverage of your choice (unless you already have)
Step 2. take a deeeeeeeeep breath
Step 3. realize it can be removed and may actually not even be tight in the threads
I am guessing a long metal tube the size of the thread hole with a long drill bit inside it would be a good start followed by an easy out with a long extension. Your engine is definitely not ruined and you WILL get the small bit out and have a happy ending- just don't rush it and think it through. Likely you hit some liquid at the bottom 1/4 of the threads and it snapped there.
I have had the same thing happen in a 4.0 AJ6 engine when I re-used a head bolt as per the Jaguar recommendation.
I torqued the bolt and then performed the 'torque-to-yield' rotation when it 'snapped'.
I spayed some solvent into the hole and blew it dry.
I applied a dab of 'two-part' epoxy to the end of the bolt and re-inserted it into the hole to feel for the mating surfaces to lock together.
I let the epoxy setup overnight and gently removed the broken end in the morning!!!!!
New head bolt installed and finished the repair!!!!!!!!!!!!
I have had the same thing happen in a 4.0 AJ6 engine when I re-used a head bolt as per the Jaguar recommendation.
I torqued the bolt and then performed the 'torque-to-yield' rotation when it 'snapped'.
I spayed some solvent into the hole and blew it dry.
I applied a dab of 'two-part' epoxy to the end of the bolt and re-inserted it into the hole to feel for the mating surfaces to lock together.
I let the epoxy setup overnight and gently removed the broken end in the morning!!!!!
New head bolt installed and finished the repair!!!!!!!!!!!!
bob
Thanks very much for the advice and info! The bolt broke because I think I over tightened it. I'm hoping the 2 part epoxy is strong enough to undo the bolt. Will any epoxy suffice? Should I try JB Weld ? What about stud mounted on top of the broken bit and capped off with a nut?
Step 1. grab adult beverage of your choice (unless you already have)
Step 2. take a deeeeeeeeep breath
Step 3. realize it can be removed and may actually not even be tight in the threads
I am guessing a long metal tube the size of the thread hole with a long drill bit inside it would be a good start followed by an easy out with a long extension. Your engine is definitely not ruined and you WILL get the small bit out and have a happy ending- just don't rush it and think it through. Likely you hit some liquid at the bottom 1/4 of the threads and it snapped there.
First of many adult beverages on the way....
I thought I did a thorough job of blowing out the holes of any moisture. I think my torque wrench might be malfunctioning?
I'll be doing my research because I'm sure I'm not the first to f-up like this. Thanks for the advice and adult beverage encouragement
If you don't feel comfortable doing the extraction take it to a machine shop preferably an automobile engine machine shop. Believe me they have seen this before.
Those more knowing than me can correct me, but I don't think the bolts can "bottom" out with the head installed. Definitely agree though to replacing bolts with all new. (LS bolts are less $$ FYI)
I might be missing something, but wouldn't it be easier to remove the broken head bolt with the head off. I can't tell by the photos but if the bolt broke in the head and not in the block you might be able to remove it with vise grips.
I used a bolt extractor kit I found on Amazon. The tricky part was getting to the bolt as it was about 2+ inches below the deck surface. Center punched the bolt then used a small section of plastic tubing around the drill bit to keep it as centered as possible. Frequent checking with the boroscope and compressed air to keep it clear. Once I got about 3/4 inch deep I tapped the extractor (barely rising above the block deck!), once secure it came out like butter.
Now waiting for the metal head gaskets to arrive to (finally) finish the project.