I broke a tap off in the rear driver's side exhaust bolt hole

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greymouser7

greymouser7

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Am going to have to pull the cylinderhead, from the engine, in the car.

I could use some advice on getting the tap out.

It's small enough, does it still get drilled in the center.

I saw something weird at work called a thread extractor, with tines that pulled on it, but that is avague memory-am not sure how it worked at all.
 
Good luck trying to drill a tap; usually that doesn't work out well.

If you don't already have an extractor set, I'd recommend the Snap-on set. It's expensive, but has left handed drill bits that will sometimes grab the broken piece and back it out without having to use an extractor. If you do drill it, drill it all the way through so if the extractor breaks, you can punch it into the head and remove it after you get the tap out.

Good luck.
 
A tap is made out of very hard (brittle) material. If the tap isn't in too deep you can take a sharply pointed punch and chip the tap into small pieces. It takes time and care but I've done it many times. You just keep hitting the tap (in it's weakest places) using a hammer and the pointed punch. The only thing that will drill out a tap is a carbide drill bit...it the carbide bit breaks off in there you're in a heap of trouble!!
They do make a tool with fingers that go into the flukes of the tap, but if the tap is really stuck in there it might not break loose.
Also sometimes you can (using the pointed punch) carefully force the tap to turn backwards (CCW), once you get it loose you can grab it with needle nose. If you take your time and do it carefully you can always get the tap out of there!!!

treblig
 
Pull the head off, find a machine shop that has EDM; Electrical Discharge Machining; you won't find a drill bit hard enough to drill a tap, OR, a thought that just came to mind is use an acetylene torch to "blow" the tap out; torch won't hurt the cast iron and the slag won't stick
 
A masonry bit does have carbide silver soldered on. It would cut the tap but its tip grind isn't just right for center cut in steel. If you can hang the exhaust manifold back in place and use that for a drill guide, you might push a 1/4 inch masonry bit through the tap. I would try shattering the tap first, if I can get a good hammer blow on it.
 
RESCUE BIT!! made to drill Hardened steel! Research it!!! works good! Not expensive! It will drill a tap, I used it to do just that. [ame="https://www.youtube.com/watch?v=FkIH7DhQJzA"]The Original Rescue Bit - YouTube[/ame]
 
Try the easy stuff first lube it up good and try some slim needle nose pliers to back it out or a thin punch. If you get it to start to back out blow air and keep lubing it up.
 
Dang you guys are stubborn. Im telling you how to fix it, I wont say anymore. You think im lying?
 
I bet it's stuck in there pretty good. Maybe try to heat it with a torch if you plan to remove it with the threads still in tact...
 
Contact your local snap on dealer and purchase a broken tap extractor. I have dealt with this situation myself before , and the tool saved a lot of time and headache. But like treblig said it might not work , but worth a shot before cylinder head removal.
 
just thinking aloud here, but the hole he mentioned goes into a water jacket no?
would that alone be enough reason to pull the head and do this on a workbench, rather then risking sending chunks of tap into the water jacket, and eventually, into the water pump?
 
diymirage said:
just thinking aloud here, but the hole he mentioned goes into a water jacket no?
would that alone be enough reason to pull the head and do this on a workbench, rather then risking sending chunks of tap into the water jacket, and eventually, into the water pump?
Click to expand...
You for sure are going to have to have head off the engine. Drill out tap with the bit I have mentioned, retap and put in a helicoil to get back to the stock size.
 
had that happen to me back in the early 90's. 360 was down in the car already, I was totally bummed of course. A buddy of mine who was and still is one of the best multicraft guys I know helped me out. He said, "you trust me"? I said sure so he took my torch, heated the broken stud and blew it to the water jacket!!!!! I tapped it to 3/8 and never looked back.!!! I'da cut a chunk out of the head hahaha!!!
 
greenswinger said:
had that happen to me back in the early 90's. 360 was down in the car already, I was totally bummed of course. A buddy of mine who was and still is one of the best multicraft guys I know helped me out. He said, "you trust me"? I said sure so he took my torch, heated the broken stud and blew it to the water jacket!!!!! I tapped it to 3/8 and never looked back.!!! I'da cut a chunk out of the head hahaha!!!
Click to expand...
This will work because of the high carbon centent of the steel that the tap uses. Blows right out. :burnout:MT
 
I was impressed !!!! Running these heads on the 360 in the Dart today (freshened of course)
 
Dang, I wish I saw this thread earlier. I sell tap extractors. tmm
 
I had a similar problem with one of my exhaust bolts that went into the water jacket. I ended up snapping off a cobalt bit in an attempt to drill it out. After trying multiple methods, I finally got it out. I used a metal cutting carbide bit. Not a masonry bit; I tried that like was suggested, but the tip is way too blunt. Ordered one from eBay since they were not available to me locally. I was able to drill out the cobalt bit fairly easy, then I hollowed out the bolt with a tapered bit on my die grinder, then I tapped out the remaining shell of the bolt. Pictures here: http://www.forabodiesonly.com/mopar/showthread.php?t=272140 good luck, take your time.
 
I blew one out with the torch, got it red then blasted it & it came back out so quick and so fast, I was impressed (& relieved)!
 
I have had some success welding a nut over the broken tap or bolt and using that to back it out. It sticks to the steel but not the cast, at least not very well.....
 
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