Hey everyone, im new here so ill start with this issue. I am in the process of changing my head gaskets and as I torqued off a driver side head bolt it broke about 1/3 of the way down into the bolt hole. I have about 1/3 thread left on the head bolt that is. Is this enough thread to securely fasten my head gasket without any leaks or problems?... because the bolts where heat welded to the block from years of use and they are a pain to get out to begin with. I cant imagine tapping one out. Any input would be greatly appreciated. Thanks guys.

 

soak and re soak with pb blaster for a day or two, then your going to have to try and eazyout it out. it may be like you said and they were corroded in or could be that someone re used the head bolts before and thats why it broke. anyways i would get it out, if gm thought they could get away with one short bolt and not compromise the the motor they would.

 

I have heard some bad things about alot of the bolt removal tools like they snap easily and as you know this bolt is really torqued down in there, probably around 50lbs plus aging and corrosion. Personally I have never had to use one so far but I may have to this time. Any suggestions on the best one out there or the best bang for you buck at least?

 

once broken the only thing holding it is crud. if its not crudded up then it may come out with a left hand drill bit. imo the square shank easyouts are the strongest and best to use. make sure you center punch the busted bolt before drilling. dont use to big a bit/easyout or it will push the walls of the bolt out into the block making it harder to move.

 

Get a left hand drill bit. Try to spot the bolt with a center punch. In many cases the vibration and heat combind with the twisting action of the drill will free up the bolt and the drill will walk it right out. I have removed dozens of broken head bolts with this process. Low speed high torque drill either a hvy plug in style or an air drill work best.The tuff ones are the small broken off exhaust bolts in the heads that have been sitting. Those are about the only ones I have to use heat on to get.

Not getting the bolt out is not an option. To end up with a usable motor that has to come out. I don't think it is a requirment on your motor but since you are having this issue you should replace all your head bolts.

 

Well I tried it all guys and nothing worked. It broke all left hand drill bits that I tried. For some God forsaken reason it was just stuck. I drilled it out to attempt a tap for a larger bolt and it stripped every tap i put to it. Im not a rookie tapper so it is just condemned to remain there. I went ahead and put the head back on using extra RTV and about 4 extra lbs of torque on the wrench. I have been driving it for a couple of weeks now with no issues, overheating or oil/water mixing. I do know it is doomed to fail eventually but that will just give me reason to convince the wife that it is time for a v8 swap. Until then, ill run it in the ground. Thanks for the help guys.

 

That will not last at all. Worst than that you never use rtv on a headgasket D'OH! Take the block out and take it to a machine shop.

 

You did center the drill with a center punch? You must be using cheap tools. Cast iron will become more machinable with age and they had not problem taping it when the engine was made. The bolt can not be too hard to drill. We do not make bolts out of steel that can get that hard.