We broke off a tap in one of the exhaust manifold bolt holes in the head of the 318 we're building. It's recessed about 1/8". We've tried to back it out with a hammer and punch but there's nothing to catch against. Anyone have any suggestions? Or are we out of luck?

Thanks,
Ken

start a small pilot hole with a small drill bit then reverse the drill and take a lefthand drill bit a size larger see if that will back it out....

I have had good luck with my plasma cutter. Get set up hit it straight on and pick out the pieces and re-thread it.

If you have a welder you can weld something like an allen wrench to it & twist it out.

Another thing that works is a cutting torch - if you have iron heads.

Heat the tap up & blast the oxygen & it will blow out of the hole. Not recommended around nice paint & proper safety procedures should be taken.

you can buy tap extractors but there a 50/50 shot, good luck drilling it out unless you have a carbide drill, depending on how much you broke off in there you can take a punch and just keep hitting the tap with the punch, the taps are so hard they will break up in little pieces, usually works if the whole tap isnt stuck in there. hope this helps, good luck!

Ken, is it on the work bench or in the car? This may sound stupid to ya, but do you know why the tap broke. What I'm asking is did it bottom in the hole, broke from cleaning and not backing it out, or some kind of side pressure that was put on the handle which caused it to break? Blow it out with air and use some Blaster on it to try and loosen the chips, tap back and forth with a punch or use an allen wrench to make a punch . There are "tap extractors " based on the number of flutes on the tap, these will normally work if the tap hasn't bottom in the hole. Or find a shop in your area that has a Tap Blaster . Just keep working on it , Good Luck Kev

Try shattering it with the punch.

put the smallest tip on your oxy/acet torch and heat it cherry red then hit it w a blast of ox w the cutting handle. It'll blow right out of there.

If the tap is siezed up and broken off in a recessed, blind hole, your best bet is to break it into little pieces with a hammer and small punch.

You may want to try a tap extractor first, however.

Broken tap hey ouch, if it isnt bottomed out,I like to shatter them with a punch and hammer like the rest have said. I have never had much luck with tap extractors. if shattering does not work maybe you know of a machine shop with a EDM that could burn it out. Ed

Thank you for all of the replies. The engine is assembled and sitting on the stand. We were cleaning the threads in preparation of installing the exhaust manifolds. The tap hit the bottom of the hole and then broke. I swear I didn't apply any pressure but I must have applied at least some side pressure.
I don't have a torch, so I'll try the shatter method first and then look into the tap extractor of that doesn't work.
Thanks again,
Ken