Broke my head bolt @#%!

[spitfire5454]

update: After welding the nut on and trying, the bolt snapped again. at this point i was tired of messing with it so i just drilled it out and put a helicoil in it. Went perfectly. I probably shouldve done this to begin with, but i get a little nervous drilling into my heads. But it worked out fine, so now i can get on with my other supercharger repair buisness. Thanks for the help. Oh yeah, are the head bolts special or something, or can i just use a grade 8 hex bolt?

[newthings]

I am surprised the bolt did not come free with the load off.
The lesson is to run a tap down every hole and use Never Seize or other thread lube anti corrosion product on every bolt. You will not get a true torque reading without a thread lube. In critical applications, for the first pass in tightening I torque to about half load and back off twice and then turn to the target value.
Good luck.
Roy

[Rene M]

I am surprised the bolt did not come free with the load off.
The lesson is to run a tap down every hole and use Never Seize or other thread lube anti corrosion product on every bolt. You will not get a true torque reading without a thread lube. In critical applications, for the first pass in tightening I torque to about half load and back off twice and then turn to the target value.
Good luck.
Roy

I have " for the most part" stopped using head bolts for this reason and have moved most of my motors to head studs.. no broken bolts, a better and more even head torque, less failure or leakage from head gaskets, usally cheeper to get a set from ARP than factory head bolts. If you read the fine print , the factory does not recommend the reuse of head bolts, Very few do.
Just some food for thought.

[psychos2]

I have " for the most part" stopped using head bolts for this reason and have moved most of my motors to head studs.. no broken bolts, a better and more even head torque, less failure or leakage from head gaskets, usally cheeper to get a set from ARP than factory head bolts. If you read the fine print , the factory does not recommend the reuse of head bolts, Very few do.
Just some food for thought.

He is talking about the bolts that hold stuff to the head not the actual head bolts. shawn

[Rene M]

He is talking about the bolts that hold stuff to the head not the actual head bolts. shawn

oops my bad.. sorry to stick my nose where it does not belong. I saw head bolt and as a tech i think head bolt not a bolt somewhere on the head.