Removing broken bolts: any special tips?

[RC92234]

“A series of unfortunate event” for sure, but you have a great attitude about moving on and getting the problem resolved. Good luck with getting it done and getting your car back on track.

Thanks -- gotta keep trying to move forward, right?

 

[RC92234]

100% credit to the person who posted this on the MeWe "All Mustangs" group page.  Gotta find the humor to keep up the effort, right?

 

[boilermaster]

RC92234,

Have to agree with most of bentworker has to say.

I have used tap exractors in the past with pretty good success, however you have to ask yourself (why did the tap break in the first place ?)

you CANNOT expect the tap to do it's job if the hole is drilled off center.

a magnetic base drill would have done wonders here !

I would suggest at this point , that you remove the timing chain cover and carefully clean up the old gasket material so you can better see where the bolt centers are or (were).

Then and only then attempt to use a tap extractor.

Ask yourself (how much torque was I applying when the tap broke ?)

Find the angle of the broken tap before attempting to use a tap extractor.

If you were NOT using a lot of torque when the tap broke, you might just get lucky.

Probably shouldn't tell anyone this. but I once removed a broken tap (miles out in the woods) by using the remaining piece of tap and pieces of a hex key and 2 nuts of the tap size, my buddy said the tap just broke for no reason.

Yes it came out pretty easy.

An old machinist once told me , if you drop a tap on a concrete floor, to throw that tap away, or it will bite you.

if you get to a point where you are going to try to use a heli-coil, I might suggest using the water pump as a drill guide (providing the remaining threads are clean. and leave timing cover (OFF)  or NOT using the 3 threaded holes in the cover.

Once you have a hole started use a magnetic base drill (even though you may have to remove the radiator.

                                                                                                    Boilermaster

 

[Don C]

Great idea on using a magnetic base drill press. I've used a variety of things to get taps out. I have some needle nose pliers that I ground down to a point that work well if it's not jammed to badly. I've also broken them out with a punch, that brittleness works there, too. If you use them much, no matter how carful you, are it's just a matter of time before a smaller one breaks. That's a good idea about throwing them away after dropping them.

 

[tony-muscle]

What about drilling small holes around the inner diameter of the threads?. Do this until there are no threads and you can pull the bolt out. At that point you have a bigger hole that someone i am sure will know how to fix. I did this in the past in another application where i was able to simply tap a bigger hole after all the little holes through the threads. It took a lot of work and a few bits to drill around the rusted bolt with broken extractor.

Sent from my SAMSUNG-SM-G930A using Tapatalk

 

[timachone]

I found out that heat is an essential part to success for such "projects", for example on exhaust related parts as manifold bolts to heads or the pipes... 

It doesn't harm to apply some hefty beats to the bolt from time to time, using penetrating oil, blowing with a propane torch and a short move in the opposite direction than loosening it... Be patient is another important but difficult advice - don't ask why I know... 

But now you are in a complete different boat, I am sorry about to hear  :-/

 

[Vinnie]

The first time this happened to me I punched a dimple in the middle and then drilled through the middle with a tiny drill. I increased drill size a few times and my last drill had a diameter just under the diam of the thread and it rotated anti clockwise. You have to be able to work rather precise but that goes for every solution you're going to use I believe. If the bolt doesn't come out while drilling you can peel the remaining metal out since it's gotten very thin.

 

[timachone]

The first time this happened to me I punched a dimple in the middle and then drilled through the middle with a tiny drill. I increased drill size a few times and my last drill had a diameter just under the diam of the thread and it rotated anti clockwise. You have to be able to work rather precise but that goes for every solution you're going to use I believe. If  the bolt doesn't come out while drilling you can peel the remaining metal out since it's gotten very thin.

+1

 

[RC92234]

The first time this happened to me I punched a dimple in the middle and then drilled through the middle with a tiny drill. I increased drill size a few times and my last drill had a diameter just under the diam of the thread and it rotated anti clockwise. You have to be able to work rather precise but that goes for every solution you're going to use I believe. If  the bolt doesn't come out while drilling you can peel the remaining metal out since it's gotten very thin.

+1

There actually were three and that is exactly what we did successfully on one of them. It was also far easier to access.

All of the above are good suggestions but a lot more difficult when put to practice. I work in a carport in my driveway; I don’t have a shop.  For example “use a punch and make a dent to start the drill”: working in a space about twelve inches wide at roughly my kneecap level, even using using a 3# sledge, no bueno. That old steel is hella’ hard. So instead I used a pointed dremel grinding tool to get the start dent.

And yeah, drill a small hole, increasing in size, is fine except except even using cobalt bits you’re likely to eat up quite a few. And handheld tools, again, used bending over and applying force at about kneecap level, precision and alignment are, well, “challenging”.

Like I said when I started the thread, I’ve met my match    The good news is I’ve found both a mechanic and machine shop to get me outta this mess.

 

[Vinnie]

Yeah, the bolts being in the front doesn’t help much. Was it an option to remove the radiator and grille for easier access?

Glad you’re gonna get it done, this stuff can be very frustrating.

Hope it’s all in the past for you soon!

 

[boilermaster]

RC92234,

In hindsight, it might have been an option to have just cut the heads off of all the bolts that did not want to come loose.

I have only been smart enough to do this only ONCE !.

Then you might have seen how thin the bolts have gotten over time.

All of us that have changed a lot of water pumps on ford engines have seen how thin the bolts tend to get with corrosion.

How many have done this very same water pump job and said to themselves ( wow, I really got lucky there)

You were not lucky.

Let this be a lesson to our members that these are 40 something year old engines we are working on !

Please keep us posted on what your mechanic and machinist intend to do, and your progress.

                                                                                          Boilermaster

 

[Carolina_Mountain_Mustangs]

Sorry for getting in on this one so late. 

I was a tool & die maker for many years so I have had to deal with broken bolts, taps and tape extractors since back in the 1960's. 

MY FIRST COMMENT IS NEVER NEVER TRY TO USE AN EXTRACTOR TO REMOVE A BROKEN RUSTED IN BOLT. At best they are a 50 - 50 chance of breaking them on smaller than 1/2" bolts. Rusted in bolts should always be drilled. 

Yes if you have fresh metal and break a bolt using a L.H. drill bit will sometimes yield the bolt screwing itself out by the drill bit grabbing and screwing it out. 

Once you have a broken tap or screw extractor you have to get creative for sure.

Like stated in one of the comments. It is probably best to use a pencil grinder or dremmel with a carbide bit to get the center of the bolt or even use a ball carbide burr and get into the bolt far enough to guide the drill bit. You should make you a drill guide on a milling machine or bench drill press. That is drill a straight hole through at least a 1" thick piece of steel to use as a drill bushing for  the tap drill bit to be used. You locate the drill bushing over the hole to be drilled and clamp in place using existing holes around the area. This keeps the drill centered and straight which is very important. 

I once spend probably 6 hours hand grinding an oil galley plug out of a flathead V-8 block. The plugs were tapered and the allen socket stripped out. So I drilled the center out and then took carbide burr and slowly ground out until I could see the tips of the threads in the block then picked the pieces of the plug out with a scribe. 

Now that you have the broken tap I would pull the block out. As has been stated you will need to locate a shop with a Tap Buster or EDM, Electrical Discharge Machine. Not many will have one with a Z travel enough to fit a block under the ram. 

The EDM is only known by that name. It has nothing to do with a laser it is and electrical current and a dielectric fluid to wash out the burned steel. 

I made a tread burning attachment for one of our EDM machines while working in the shop. Sometimes we needed to go to larger bolts in hardened steel parts. If you wanted a 1/2" -13 thread you make carbon electrodes on the lathe with 13 threads per inch but small enough to go into the tap drill size hole. The attachment I made allowed you to get the electrode in the hole and stop the downward travel and then start the electrode in an orbit that expanded and burned the threads into the hardened steel.

Now back to the block.

I see you used a 4 flute tap. Never use a 4 fluted tap. They break much easier. I saw in one post they suggested to not use hardware or harbor freight taps. I totally agree with that statement. If you are drilling out a broken screw go buy American made drill bits that are High Speed or Cobalt steel. Also buy two flute plug taps that are titanium coated. A plug tap has the threads gradually going to full depth. A bottom tap has a very short lead in and then is cutting full threads and will chip easily. The titanium coating prevents the tap from sticking as easily. Also taps come in different sizes. That is designated the the GH size. Example would be a GH-3. That would be .0015" over size. Each number up is .0005" over the nominal bolt size. I would got with GH-3.

I have used a center punch to chip out a broken tap but not deep in the hole like you have. The EDM is about the only solution you will have. You do not pound it with a 2 lb. hammer you use a small jewelers hammer and peck on the tap and chip it out. 

A carbide drill bit does not like an interrupted cut like the tap will be and when you break the carbide then EDM is only solution. 

The EDM will cost you probably $250 and hour a Tap Buster much less. See if you can find a fellow car nut that has a shop that might help a fellow car nut out.

I do not think you will find an EDM with enough Z travel that would be huge to fit the block under.

It looks like you might have to drill the hole oversize and plug it then drill for the correct bolt size. Would need to pin the plug in or spot weld it. Probably pin since cast iron to a steel plug. 

When drilling and taping use a cutting oil not WD-40 or regular oil. They are lubricants. Cutting fluids are there to increase the cutting ability not lubricate. 

When using a tap you need a tap handle and you need to use a taping block to hold the tap straight. You can make the taping block using a drill press or mill. If a 5/16" tap just drill a 5/16" hole in the block to guide the tap. All tool & die makers have a taping block in their tool box. Also always use a Tap Handle. You can get that at Harbor Freight it just holds the tap. If you try to screw in with a wrench you are putting all the force on one side of the tap and will break it. Tap handle you are pushing on both sides equal and less chance of breaking tap.

When taping go half turn them back up and about ever two turns remove the tap and blow out the chips. If the tap gets locked do not try to back it out using force. Go in and out short turns until the chip breaks off and the tap will turn free again. 

Patience is key never rush it. Soak the bolts for days before you go breaking them off.

When you go back together with any fasteners use a never seize on the threads. This is on any bolts outside the crankcase. Never use inside where the oil is. It is usually glass beads, copper or aluminum flakes. 

On thermoset plastic molds and die cast tooling you break lots of bolts even using the never seize. I have had to deal with hundreds of broken fasteners and taps and have always got them out. 

When I work on and engine every tapped hole in the whole block gets a tap ran into it to clean the threads out and every fastener gets anti seize on it. You can get at any automotive parts house this is one brand they usually have. There is also copper flake this is aluminum.

 https://www.amazon.com/Permatex-80078-Anti-Seize-Lubricant-Bottle/dp/B000FW7VGE/ref=asc_df_B000FW7VGE/?tag=hyprod-20&linkCode=df0&hvadid=312181776237&hvpos=1o1&hvnetw=g&hvrand=3035487797575239685&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9051981&hvtargid=pla-492337354522&psc=1

 

[RC92234]

Sorry for getting in on this one so late. 

I was a tool & die maker for many years so I have had to deal with broken bolts, taps and tape extractors since back in the 1960's. 

MY FIRST COMMENT IS NEVER NEVER TRY TO USE AN EXTRACTOR TO REMOVE A BROKEN RUSTED IN BOLT. At best they are a 50 - 50 chance of breaking them on smaller than 1/2" bolts. Rusted in bolts should always be drilled. 

Yes if you have fresh metal and break a bolt using a L.H. drill bit will sometimes yield the bolt screwing itself out by the drill bit grabbing and screwing it out. 

Once you have a broken tap or screw extractor you have to get creative for sure.

Like stated in one of the comments. It is probably best to use a pencil grinder or dremmel with a carbide bit to get the center of the bolt or even use a ball carbide burr and get into the bolt far enough to guide the drill bit. You should make you a drill guide on a milling machine or bench drill press. That is drill a straight hole through at least a 1" thick piece of steel to use as a drill bushing for  the tap drill bit to be used. You locate the drill bushing over the hole to be drilled and clamp in place using existing holes around the area. This keeps the drill centered and straight which is very important. 

I once spend probably 6 hours hand grinding an oil galley plug out of a flathead V-8 block. The plugs were tapered and the allen socket stripped out. So I drilled the center out and then took carbide burr and slowly ground out until I could see the tips of the threads in the block then picked the pieces of the plug out with a scribe. 

Now that you have the broken tap I would pull the block out. As has been stated you will need to locate a shop with a Tap Buster or EDM, Electrical Discharge Machine. Not many will have one with a Z travel enough to fit a block under the ram. 

The EDM is only known by that name. It has nothing to do with a laser it is and electrical current and a dielectric fluid to wash out the burned steel. 

I made a tread burning attachment for one of our EDM machines while working in the shop. Sometimes we needed to go to larger bolts in hardened steel parts. If you wanted a 1/2" -13 thread you make carbon electrodes on the lathe with 13 threads per inch but small enough to go into the tap drill size hole. The attachment I made allowed you to get the electrode in the hole and stop the downward travel and then start the electrode in an orbit that expanded and burned the threads into the hardened steel.

Now back to the block.

I see you used a 4 flute tap. Never use a 4 fluted tap. They break much easier. I saw in one post they suggested to not use hardware or harbor freight taps. I totally agree with that statement. If you are drilling out a broken screw go buy American made drill bits that are High Speed or Cobalt steel. Also buy two flute plug taps that are titanium coated. A plug tap has the threads gradually going to full depth. A bottom tap has a very short lead in and then is cutting full threads and will chip easily. The titanium coating prevents the tap from sticking as easily. Also taps come in different sizes. That is designated the the GH size. Example would be a GH-3. That would be .0015" over size. Each number up is .0005" over the nominal bolt size. I would got with GH-3.

I have used a center punch to chip out a broken tap but not deep in the hole like you have. The EDM is about the only solution you will have. You do not pound it with a 2 lb. hammer you use a small jewelers hammer and peck on the tap and chip it out. 

A carbide drill bit does not like an interrupted cut like the tap will be and when you break the carbide then EDM is only solution. 

The EDM will cost you probably $250 and hour a Tap Buster much less. See if you can find a fellow car nut that has a shop that might help a fellow car nut out.

I do not think you will find an EDM with enough Z travel that would be huge to fit the block under.

It looks like you might have to drill the hole oversize and plug it then drill for the correct bolt size. Would need to pin the plug in or spot weld it. Probably pin since cast iron to a steel plug. 

When drilling and taping use a cutting oil not WD-40 or regular oil. They are lubricants. Cutting fluids are there to increase the cutting ability not lubricate. 

When using a tap you need a tap handle and you need to use a taping block to hold the tap straight. You can make the taping block using a drill press or mill. If a 5/16" tap just drill a 5/16" hole in the block to guide the tap. All tool & die makers have a taping block in their tool box. Also always use a Tap Handle. You can get that at Harbor Freight it just holds the tap. If you try to screw in with a wrench you are putting all the force on one side of the tap and will break it. Tap handle you are pushing on both sides equal and less chance of breaking tap.

When taping go half turn them back up and about ever two turns remove the tap and blow out the chips. If the tap gets locked do not try to back it out using force. Go in and out short turns until the chip breaks off and the tap will turn free again. 

Patience is key never rush it. Soak the bolts for days before you go breaking them off.

When you go back together with any fasteners use a never seize on the threads. This is on any bolts outside the crankcase. Never use inside where the oil is. It is usually glass beads, copper or aluminum flakes. 

On thermoset plastic molds and die cast tooling you break lots of bolts even using the never seize. I have had to deal with hundreds of broken fasteners and taps and have always got them out. 

When I work on and engine every tapped hole in the whole block gets a tap ran into it to clean the threads out and every fastener gets anti seize on it. You can get at any automotive parts house this is one brand they usually have. There is also copper flake this is aluminum.

 https://www.amazon.com/Permatex-80078-Anti-Seize-Lubricant-Bottle/dp/B000FW7VGE/ref=asc_df_B000FW7VGE/?tag=hyprod-20&linkCode=df0&hvadid=312181776237&hvpos=1o1&hvnetw=g&hvrand=3035487797575239685&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9051981&hvtargid=pla-492337354522&psc=1

Thanks for the tips, especially the reassembly ones.  Also, agree on Harbor Freight tools:  not for heavy-duty challenges!

As only-a-driveway-mechanic, I can pretty much guarantee I won't be doing this again.  I don't have enough years left in me and I want those to be spent *enjoying* the car, not under the hood.