Bolt broke off how to remove a piece still in the hole?

[mrzabala]

Just finished sealing and adding a new valve cover gasket. I tightened the bolts to 7lbs and waited a whole day to cure. Problem is theirs a little leak in the front and I went to 8lbs on all the bolts. Note that at the front of the valve cover their are 3 bolts(middle front and 2 at the corners) that where already loose threaded. Guess previous owner torqued it down without realizing its an aluminium head. Anyways I used some bolts that fit and fixed the middle and the one to the left with bolts I had in storage. As for the one to the right, it snapped leaving a little more than 1/4" in the hole. I also have a nut at the bottom to hold the bolt down which is now screwed in with the broken piece. Is thier a way to take off the broken piece without having to remove the whole thing(replace the gasket and such)? Thanks for the help Ill try and figure something out while I wait for an answer.

[rogoman]

The only way to remove the broken bolt is to remove the valve cover. If the broken bolt is flush with the head surface, then you can drill a pilot hole into the center of the bolt and use an 'easy out' to remove the bolt.

[mrzabala]

Thanks for the advice, the broken piece is just above the head. I ended up drilling into it but my dremel bits broke off.. Then I used a circular disc to cut off the bottom piece and worked perfectly. I only had one nut left(that sounds odd) and bolted another bolt in and works great!! Was really scared for a second that I wouldnt be able to run my car without it leaking. I cleaned the bottom of the engine and ended up using 1 role of towel and a pound of grim and oil.... Guess thats what happens when the bolts are loose and oil starts leaking.