My intake manifold gasket leaked allowing corrosion on one of my manifold bolts, which subsequently broke as I was attempting to remove it. The break occured about 5/8" above the block. What is the best way to remove the remainder of the bolt?

Thanks,
Mike

 

spray rust remover around the bolt let it sit for awhile then use a stud extractor to get it out.

 

That's what I thought it was going to take.

 

dont use one of those bolt extractors that require you to hammer down onto the bolt.
you might warp the threads inside from all of that banging.

i bought a junk extractor that simply doesnt work for the 9.8 grade bolts.
you are supposed to sand it, tap it in the center with a nail or something to create a dent in the middle, then drill a small hole down into the middle of the bolt.
once the hole is there, you can put the extractor in and hope it bites the bolt.
but
truth is, the extractor is supposed to CUT into the bolt to get its grip.
there are only two ways to get a grip:
1. the extractor is sharp enough to cut into the metal (chances are it isnt, or you will pay a premium price for the hardness ..and then it might only work two or three times.. )
2. the extractor expects you to hammer it into the bolt to create the cuts.
when you hammer it in, it is supposed to help create the indentations that give a grip to spin the bolt..
but
hammering down that hard really puts stress on the threads inside and you might strip the threads before the bolt comes out.. and if you are messing up the threads, they will become detached and make the bolt even harder to spin.
when you do finally get it out, the hole will be completely stripped and wont have any threads.

the professionals might do it this way because since the hole is bare, they can simply switch to a tap and put new threads in (switching to metric size or whatever the next size up is)

i broke a bolt on the head for the camshaft bearing cap.. i refused to tap really hard on the metal, so i ended up getting a drill bit the size of the threads (compared the bolt.. and if it is a hair more, no problem)
drilled the bolt out because my bolt snapped BELOW the surface and i had the outside rim to guide me into the hole straight.
once i got to the bottom, i used a tap to make new threads.
had to drill the camshaft bearing cap to make the hole bigger for the new bolt.. but after that, it went together like a breeze.
dont put the bolt into the new threads until you are ready to leave it.
that means dont play with it, just screw it in once when it is time for it to hold.
exotic metals can prove to be different, and this is a machinists job.. and i dont expect general consumers to run into these metals often.
it seemed my bolt shoved the walls good on the way down.. so when i realized it would be a tight fit for the new bolt.. i didnt want to put the bolt in and pull it out, only for the hole to lose its shape.


now..
for 5/8th of an inch, you should be using a rag with a hole in it to expose the broken bolt.
wet the rag with water to prevent it from catching on fire (only if it will catch on fire easy)
then get yourself a nut that either fits over the bolt.. or sits on top of it.
get a welder and start your tack against the bolt where it touches the nut, then proceed to fill in the center of the nut while it is nice and red hot.

if the nut is too big and it is hard to get your first tack started, you could always use a thin washer to weld onto the bolt shaft.
then weld the nut onto the washer.
if the washer is too big, then you could cut it in half or less to make it fit.
the only problem is when the washer metal is too weak and it doesnt help hold the bolt.
but
you are only using the washer to touch the bolt for certain.
then use your weld to touch the weld (and washer too) to give it a 'red hot mix'
shouldnt matter if the washer weld cools a little bit, as long as it is still fresh.
it is hard to add the nut and weld it to the washer/bolt weld while it is still red hot.
but if you do, it should help the mixture.

let it cool so it is hard.
the rag is there to prevent you from welding onto the block.
with the new nut on top, the bolt should spin right out like normal (unless the nut isnt perfectly center).

doing it the weld way will save your threads and the hole.
you wont be stuck with a new drilled hole that isnt perfectly centered.
it is always the recommended method to try first when the bolt is an 'out-y'

i cant really suggest using a stick rod weld, because the stick rod might melt too much and drip onto the block.
but
if that does happen, you could always get in there with a small dremel grinder to 'disconnect' the weld from the block.
either sand it down or cut it (or both).


if you do have to drill the hole out.. dont worry too much if the bolt is not perfectly centered.
you get about 1mm of room to play, just drill out the manifold hole for the bolt if you need to.
and since the stock bolt broke, you dont have to worry about any washer preventing you from wiggling the bolt a little bit.
i dont remember if the lower manifold bolts have a washer, i know the top ones do.

maybe you can put a glob of weld onto the bolt stud with the rag to prevent any contact with the block.. then weld the nut onto the glob of weld.

 

Thanks for the great description on reasonable ways to solve my problem. I'll let you know how it goes.

Mike