one of the bolts from the head broke when we were taking it out. is there a way to remove that bolt without damaging the block.

 

You actually broke a headbolt? Is it broken flush with the block?

 

Ditto^^ I have never heard of sombody breaking a head bolt.

 

if thats the case. grind the top of the broken bolt flat, use a punch to put a point in the center, get a left handed cutting drill and drill it out. if the bolt started to come out before it broke the drill will usually just back it out the rest of the way. if it didn't move then you will still have a starter hole to put an easyout in to get it out

 

Just keep in mind that headbolts are made of pretty tough material, so get a good supply of drill bits. May want to go to a machine shop supplier and pick up some solid carbide bits.

 

well the bolt is inside the hole and yes we r currently drilling the center of it.

 

bolt must have been in a water jacket and has serious corrosion on the tip or was seriously crossthreaded. if thats the case you'll be lucky to get it out with an ez. if all alse fails ... slowly and careful drill to one below the diameter of the bolt then tap the remaining thread material out with a sharp pointed awl. sick

 

You Guys have never heard of a broken head bolt ? C'mon it happens all the time. I've removed literally hundreds of them over the years. Be very careful not to touch the threads in the block when You drill it. If You do screw up the threads, You can but a Helicoil kit to fix that problem. It's a 7/16 coarse thread bolt ( USS thread Not SAE ). Replace all of the head bolts because if one has broken then the others can follow suit. Fel Pro and Pioneer sell head bolts. ARP sell a much better than stock head bolt kit. I always use them in performance engines.

 

Cobalt drills are actually a much better drill to use. I do believe they would only be available from a shop supplier though. in the machining trade we use them a lot more than carbide in these types of situations. I will use them to cut harder steels and even titanium if the situation calls for it.

the thing is that carbide has NO give and can chip and get lodged into the part. Cobalt gives and doesn't really chip. when you are doing things by hand without the steadiness of a quill or the even pressure of a machine, Cobalt is the way to go

 

Yep I agree with uncle bill just drill out the bolt and rethred the bolt hole in the block.