i broke a tap in my block!!!

[60ratrod]

ok so i obviously broke a tap in my block today. i was attempting to retap the head bolt holes so as to not break any of the bolts. i did manage to get one side completely done. so does anyone have any ideas as to how to get it out?? the hobby shop on base has some tap extractors, but none the right size. does anyone know where i might be able to pick up a 7/16 tap extractor??

[68K20 x Drill]

I have chipped them out in small pieces before.
needle nose and a small punch.
Someone who is good with a torch can blow it out of there for you, or a high tech machine shop can do it with a laser.

[60ratrod]

well the issue is is it is still in the truck. i don't really have the time to pull the block. would a machine shop have a tap extractor??

[WorkinLonghorn]

How much torque were you applying when it broke? (Trying to figure out how much you'll need to get it out).

[Scott68-93-97]

Originally Posted by 68K20 x Drill

I have chipped them out in small pieces before.
needle nose and a small punch.
Someone who is good with a torch can blow it out of there for you, or a high tech machine shop can do it with a laser.

The hole reason I got my 68 for 1500 is there was 2 broken bolts in the front of the block and one with an extractor broken off in it (good luck with a drill) a colbalt bit will work ever so slightly but will quikly kill a $20 bit since the tap is hardended I used a combo of the torch and a drill and got through, heating it up to soften the metal then using a drill while the metal is hot, also a small punch chipping at it like 68K20 said will greatly help out it takes time but it beats an expensive laser cutting bill and time to get it down there pick it up and the week they'll probably have it. Good luck

[jerry moss]

buy a high quality punch-not some overseas crap-and break the tap into pieces.were you cleaning a few threads at a time or trying to clean all the threads at once. lots of lube and only a few threads at a time, also use only high quality taps. they also make "tap sockets" so you can use a 3/8 drive ratchet.

[OLDCHEV4X4]

Man, for only chasing threads, thats a big tap to break. I always turn it in a 1/2 turn or so, then back it out a turn. You gotta get a feel for it. If it starts to get tight, Back it all the way out and clean out the flutes of the tap and the threads. I use Tap Magic, but wd40 will work too.
I wouldn't drill it out cause if the drill wanders and gets into the threads, You will have to helicoil it.
Go with the quality punch and try to tap it ccw with a hammer. Or sacrifice a pair of needle nose pliers.
I wish you lots of good luck, Its a stressfull thing when that happens.

[truckdude239]

the only way i know is drill it or tryto break it up. or like others say machince shop

[Sport/Truck]

You should be able to get an extractor at NAPA. I would suggest soaking it with PB Blaster to help with the removal.
How many flutes are on your broken tap? Make sure you get the correct remover.
s/t

[Fastfun]

Try this site

http://www1.mscdirect.com/CGI/NNPDFF...2323&PMCTLG=00

[jdwhitlo]

I've used a can of CO2 for blowing out your keyboard to freeze the tap then just hit it with a punch and it will pretty much shatter. Works well.

[odog]

Originally Posted by jdwhitlo

I've used a can of CO2 for blowing out your keyboard to freeze the tap then just hit it with a punch and it will pretty much shatter. Works well.

Best way I have found to "freeze" and break a tap is tip a little propane bottle upside down and drip the propane onto the broken peice. Then strike with a punch. it should shatter into about 6 pieces. Colder than CO2 and works great. Also good for "shrinking" pins when they are tough to slide into place.

[PanelDeland]

Brokeen taps are a pain.I've used most of the methods above at one time or another(not JDwhitlo's tho).One thing I would recommend is not to retap threaded holes in an engine.Instead use a thread chaser.Usually only 2 flutes and doesn't take metal out.They will allow you to get clean threads without lessening the holding surface of the threads.

[shortbed70]

They make a tool to get them out. It has three/four prongs that catch the tap on the flutes and they back out.

[Truckstr]

If the tap extractor doesn't work, you're likely to have to pull the engine/block. Before you do, find a machine shop that can/is willing/has the capability to remove the tap. I think I'd check into that before I even tried a tap extractor. If you break that... bad ju ju.

A good machine shop can remove it - maybe with a wire EDM machine. But that's $$$. That could easily offset the worth of the block itself.

Like PanelDeland said, always use a chasing tap to clean threads on already threaded holes. Live and learn...

[corn]

They break up pretty easily because they are fairly brittle. Its probably going to be a time consuming job no matter how you do it. A regular tap will break off, but a bottoming tap or thread chaser shouldnt do is so easily.

[60ratrod]

well i tried the various hardware and auto parts stores and no one had an extractor. how do i go about the needle nose route??

[Steelawork'n]

You wouldn't have to pull the enginge would you? Just pull the head and take it down to the local machine shop.

[WorkinLonghorn]

But the threads (and the problem) are in the block.The bolts just pass through the heads.

[red69ss]

I Work In A Machine Shop(not Automotive) Theres A Machine Made For Tap Removal People Call Them Tap Busters Or Hole Poppers Uses Copper Electrode To Burn Through Tap.i'm Sure Not Every Shop Has These We Use It To Put Holes In For Edm. ...........old Chev 4x4 Is Right You Have To Continiously Back Tap Out Or It Will Break Becuase Chip Binds Up The Tap. Try Heating Area And Catching Flutes With Needle Nose If You Can't Find Tap Extractor.

[Rollie396]

I feel your pain.The intake gasket was leaking in my ol s blazer (that's never happened with aluminum intakes before has it ).I was trying to delay the job of replacing the gaskets by giving the bolts a slight torque adjustment and I managed to break a bolt off.I drilled it(bit wandered slightly into the threads and the stress level doubled).Sent the easyout(my butt) in and despite being careful,snapped it as well(anuerism time).I then took a hammer and punch to it and eventually got it out.I picked out the pieces and ran a magnet and a vaccum through the valley and called it good.The threads weren't great,but they took the required torque so all worked out.That was the worst experience I've endured in awhile and it taught me a lesson as well!

[60ratrod]

i think that i might try the heating route. cause i know that metal expands when hot. so should i take the block to the point of being red or just barely red?? can i use a pluming torch for this??

[hdflstf]

Originally Posted by 60ratrod

i think that i might try the heating route. cause i know that metal expands when hot. so should i take the block to the point of being red or just barely red?? can i use a pluming torch for this??

Tap will expand at the same rate (or very close) as the block. The block is also a big chunk of metal to heat. It may help loosen things up so it's still worth a try.

[57sailplane]

man i just could not resist.

first i think that freezing it shattering it is your best bet if you cant find the proper tool to extract it.
if you cant get it out this is what i would do as a last resort.
i am not sure if it will work for a tap but it has worked many, many times for me on rusted or over torqued bolts that have broken off down in the hole or flush. i don't think a tap should be any different maybe more stubborn.

get a nut of the right size as what the bolt hole is. use a set of needle nose to hold it over the hole then place a MIG welder nozzle over hole make sure welder is set to burn at least 1/8 inch steel so you get good enough penetration. key is to burn into the tap at the beginning moving around in a circular motion fill hole all the way to top of knot so it is flush or a little crown. let it cool this is key. its what gets the tap or bolt out. it shrinks the tap or bolt down and the metal around it away. If done correctly you will get it with your first try. if not try again. i have always been successful doing this and i am not lucky or good not bragging either it just works when in a crunch. its an old timer trick. that i learned originally with a stick welder on bigger bolts at a machine shop. anyways this is only a suggestion. as i said i would try everything else first... also you are welding into cast iron so the more i think about it this will work good in your situation.

[57sailplane]

lol, i got so caught up in the heat thing that i skipped the obvious when everything is cool use wrench to unscrew the nut and hopefully the tap. lol