help with sheared manifold screws

I searched, but couldn't find a thread that addressed my issue specifically. (please point me in the right direction if you know of one.)

I recently acquired a 1977 kz1000a that has been sitting for years. I've been working on getting it on the road by going through the usual cleaning, checking, and adjusting. After cleaning and rebuilding the carbs, it became clear that the intake manifold boots were leaky. I set out to remove them (to clean and reseat them) but discovered that the upper screws on the manifolds were severely seized -- the lower ones came off fine. Using PB Blaster and an impact screwdriver, I managed to get two of them off. The other two, however, were so seized that they sheared off. Before I do anything else, I wanted to ask the forum what the next best course of action should be. I'm open to any and all suggestions. I'd be happy to provide pics or more details.

Are they sheared off flush with the head or is there enough to get a hold of?

Powerstroke_fan wrote: Are they sheared off flush with the head or is there enough to get a hold of?

One is sheared flush. The other has a about two threads worth sticking out -- not quite enough to get a ahold of of.

Find someone with a tig welder and have them weld a nut on it.
The heating and cooling along with the extra grip of the nut should help to extract the bolt.
Use some pb blaster and work it out like a tap.

If you don't have a welder, you can get a small screw extractor from NAPA. They have a small end like a punch and you just drill a small hole in the middle of the screw (so you don't hit threads) then hammer the remover into the hole and twist the screw out. At little heat will help, just be careful since its aluminum. However, if you do have access to a welder go that route.

I dont know if you have fixed your sheared bolts by now but at this stage, you have to drill a 3/16 hole in the center of the bolt and use an easey-out to screw it in counter clockwise which when seated will back out the sheared bolt. Dont get crazy with it though.

And don't use Ryobi screw extractors, I just ended up with one in my exhaust side, and it was softer than the screw, I drilled right through it. They don't stand a chance. I had some craftsman's that faired a little better. Be careful with extractors, many a thread holds the classic "i used a screw extractor, and now instead of a stuck bolt, there's a stuck extractor" line in it.

tap the easy out in with a hammer and back it and the stud out with an adjustable wrench on the easy outs square tip...easy is the key word...if the hole you drill is straight and deep enough and the hammer taps the extractor in tight...the slow hand turned wrench will ease it right out