ARP head bolt broke in block, whole thing trashed?
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From: lebanon, ohio
ARP head bolt broke in block, whole thing trashed? the center head bolt between the rockers broke, now this is by no means ARP's fault, these bolts have been used in 2 cars and have probably been torqued probably 15+ times so they've held up really well, all the other ones went in fine to 70ft. lbs.
Has anybody had this happen? I'll post results if it blows the gasket when I start it in a couple hours, I was going to stop there but this is just a junkyard piece meal motor, if something happens its not really that big of a deal, I'm building another one to go in soon anyway.
Has anybody had this happen? I'll post results if it blows the gasket when I start it in a couple hours, I was going to stop there but this is just a junkyard piece meal motor, if something happens its not really that big of a deal, I'm building another one to go in soon anyway.
Punch a centering mark and work your way up through
a series of hardened, reverse drill bits and there is a
chance you will get it to back out. Not so easy in the
engine compartment, but you should be able to do it
fine on the bench. Buy good quality (like cobalt if you
can find them) reverse bits. Easy-Outs I would stay
away from.
a series of hardened, reverse drill bits and there is a
chance you will get it to back out. Not so easy in the
engine compartment, but you should be able to do it
fine on the bench. Buy good quality (like cobalt if you
can find them) reverse bits. Easy-Outs I would stay
away from.
For the punch, you can buy "transfer punches" that come in a set of finely incremented sizes. They are great for something like this because if you pick one that barely fits in the hole, it will punch the exact center of the bolt. You could always MIG weld an extension onto it if it isn't long enough as well.
If you get up to a drill bit close to the hole size, you can use a thin metal sleave around the drill pit to protect the aluminum block.
If a cobalt bit wont cut the ARP bolt, a carbide one will for sure.
If you get up to a drill bit close to the hole size, you can use a thin metal sleave around the drill pit to protect the aluminum block.
If a cobalt bit wont cut the ARP bolt, a carbide one will for sure.
