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Tap broken off in exhaust manifold head stud hole...

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4gfun

Supporting VIP
2,009
55
Dec 10, 2007
Ask Me, Virginia
....and unfortunately it is the stud that is connected to the oil system!

Long story but I needed to retap the below hole. I tapped it and when I finished, I went to back the tap out and heard CRACK.

I have tried to use a center punch and then an easy out, but can't make a dent in the broken tap.

I am worried that if I drill it out, I will get tons of filings in the motor.

Do I need to pull the head, or is there another way around it?

Thanks
 

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I have welded to a tap many times. So that is the first thing I would try. Once you weld to it get the area around the tap hot then try to turn it out. Really isnt that hard to do. Still confused as to how you broke it off in there.... I tapped all of mine with a tap on my drill, maybe I should re consider that next time.....

Not sure if you noticed, but I got it out. I think I bottomed the tap out which looks like a no-no. Tap set was from autozone or advance auto. I also used vice grips since I couldn't turn the tap with the part of the kit used to turn the tap since the levers would knock into things...maybe I snapped it that way? Still doubtful because it didn't snap until the very end.
 
Lol I once overed it and saw everyone trying to suggest opinions. So no I did not see that. And I dont use cheap taps so thats probably why I am confused as to how it broke! I have had the same matco set for roughly 4 years now. Yet to break one or have one dull out
 
How big is the hole now? Small enough to add a helicoil and continue to use the 8mm stud?

I guess it is kind of tough to explain without being here. Makes it tougher since I have never used a helicoil.

Youtube here I come.

I'll try to get some pics up even if they are less than ideal.

Lol I once overed it and saw everyone trying to suggest opinions. So no I did not see that. And I dont use cheap taps so thats probably why I am confused as to how it broke! I have had the same matco set for roughly 4 years now. Yet to break one or have one dull out

I guess I have much to learn. :D

Always stinks when it is the hard way but oh well.
 
If the current hole is equal to or smaller than 21/64", then a helicoil is most definitely your best option.

http://www.dsmtuners.com/forums/articles-miscellaneous/267280-how-use-helicoil.html

The hole is going to be bigger than 11/32nds or M10 from what I can see. It is my fault for drilling outside of the tap to get the tap out.

Also need to get a right angle drill if I am not pulling the head. The length of the drill combined with the drill bit make it impossible to get my cordless in. HF should have one.
 
You should be able to fit a regular drill in there after you pull the radiator, which only takes a few minutes.

Radiator is out already. GVR4 has always seemed more cramped than a DSM....never has made sense to me. :)
 
The hole is going to be bigger than 11/32nds or M10 from what I can see. It is my fault for drilling outside of the tap to get the tap out.

Also need to get a right angle drill if I am not pulling the head. The length of the drill combined with the drill bit make it impossible to get my cordless in. HF should have one.

An option to look into at this point would be a timesert. They are a little thicker than a helicoil, so there will be more to take up the extra space of the bigger hole. I would get a good measurement of the hole currently and then look at the timesert chart and see what would work for you. I have seen people in the past do a double helicoil or a helicoil with a timesert installed afterwards to get the size of the hole back to normal, but that that is kind of shady, and i wouldn't know how it would hold up. An other option, would be to pull the head, have someone weld the hole shut and re-drill the hole. Either way there are several options, whether or not you have to go with a 10mm stud, or are able to go back to an 8mm possibly. Something that you will want to do is use a little bit of thread sealer on what ever kind of insert that you use so that it doesn't leak oil.
 
An option to look into at this point would be a timesert. They are a little thicker than a helicoil, so there will be more to take up the extra space of the bigger hole. I would get a good measurement of the hole currently and then look at the timesert chart and see what would work for you. I have seen people in the past do a double helicoil or a helicoil with a timesert installed afterwards to get the size of the hole back to normal, but that that is kind of shady, and i wouldn't know how it would hold up. An other option, would be to pull the head, have someone weld the hole shut and re-drill the hole. Either way there are several options, whether or not you have to go with a 10mm stud, or are able to go back to an 8mm possibly. Something that you will want to do is use a little bit of thread sealer on what ever kind of insert that you use so that it doesn't leak oil.

What about going with a bigger stud...like M12 or M14 if needed? At some point, I will run into limitations but don't see why not. Thoughts?
 
What about going with a bigger stud...like M12 or M14 if needed? At some point, I will run into limitations but don't see why not. Thoughts?

That is an option if you have enough room to get a nut on it. One thing to take into consideration is that the bigger the hole, the thinner the casting will be around the stud.
 
That is an option if you have enough room to get a nut on it. One thing to take into consideration is that the bigger the hole, the thinner the casting will be around the stud.

I am leaning more towards this. Is there anything in the head that could get screwed up when drilling a bigger hole in that area? I know that heads have water jackets etc.
 
I am leaning more towards this. Is there anything in the head that could get screwed up when drilling a bigger hole in that area? I know that heads have water jackets etc.

You won't end up in a water jacket, but with a bigger stud you risk cracking the casting because it will become thinner at the bottom of the head. A bigger stud will also require a higher torque value to stretch the stud which is what keeps the nut from backing off. I've used a 10x1.25 there, but that is the biggest that i've got experience with. You might look for an 11mm, or even a 7/16 standard size stud. Before anything i would get a measurement of the hole to see what you are working with.
 
Have you already got the engine/trans assembly jacked up for more room to work with the head?

No, I figure that still wouldn't allow me enough room to not have to buy a right angle drill. The right angle drills over at HF are about $33. I will probably just get one, unless you think jacking it up would make that much a difference.

Thanks

You won't end up in a water jacket, but with a bigger stud you risk cracking the casting because it will become thinner at the bottom of the head. A bigger stud will also require a higher torque value to stretch the stud which is what keeps the nut from backing off. I've used a 10x1.25 there, but that is the biggest that i've got experience with. You might look for an 11mm, or even a 7/16 standard size stud. Before anything i would get a measurement of the hole to see what you are working with.

Thanks for the warning. 10x1.25, that translates to an 11/32nd I believe. an 11/32nd hole will work but will probably leave an area where I drilled around the tap. 13/32 or 12x?? should more than likely suffice for that hole (making it a nice brand new one) but now I know I have to think about this based upon what you are saying.

I could take a measurement, but it would be skewed because of my idiotic additional holes around the main one. (I thought I was drilling into the tap that easy but it was the head and parts of the tap.

I figure that based upon my best guess, and paying attention to what others have said, a helicoil won't work in there. I could probably start off by drilling for 10x1.25 which we both know is ok (measured the bolt right next to it that the previous owner put in and that's what it was).
 
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Maybe, I haven't seen a galant before, but it might be worth a try to pull the driver side mount and the through bolts of the front and rear roll mounts.
 
Ah this happened to me too! Last time I bought a cheap tap.

I couldn't tell from the picture but are any of the flutes exposed? I took a small flathead precision screwdriver and a small hammer and tapped the tap a little at a time until I backed enough out to grab it with locking plyers.

You could also try notching it with a tiny diameter dremel tool cutoff wheel and use a flat head to back it out.
 
An option to look into at this point would be a timesert. They are a little thicker than a helicoil, so there will be more to take up the extra space of the bigger hole. I would get a good measurement of the hole currently and then look at the timesert chart and see what would work for you. I have seen people in the past do a double helicoil or a helicoil with a timesert installed afterwards to get the size of the hole back to normal, but that that is kind of shady, and i wouldn't know how it would hold up. An other option, would be to pull the head, have someone weld the hole shut and re-drill the hole. Either way there are several options, whether or not you have to go with a 10mm stud, or are able to go back to an 8mm possibly. Something that you will want to do is use a little bit of thread sealer on what ever kind of insert that you use so that it doesn't leak oil.

I love time-sert. As a matter of fact I recently time-serted all the exhaust stud threads in my gst's head due to a couple of them being stripped/cracked just for peace of mind. They have this kit Big Sert that may be the solution to this problem. It works with threads that have been previously helycoil-ed and stripped again, it doesn't work well with your wallet due the price, but that is true with all time-sert kits, worth if you plan to do it over and over. Also, is the original thread completely gone throughout the whole hole or just on the surface where you had to dig to grab the broken tap (if I understood what happened correctly)?

If going to a bigger size stud remember that not only you need to fit a bigger nut in there but you also need to tighten the nut with a bigger wrench or socket.
 
Measure the hole diameter and select the minimum helicoil size that would fit. They're the best things to use in stripped aluminum holes, in my opinion. I have not used time-serts, however. If the big-sert would keep the same stud size, I would consider that route, too.
 
Had this happen with a bolt extractor that snapped off inside just like yours. Bought a few different bits and dremel attachments but no luck with anything as well.

Instead of pulling the head and after sitting there for hours drilling/tapping it with no luck, I decided to give this a try..
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It's a copper exhaust gasket from FFWD with embossed rings around the inlet that crush to seal when you torque it down. This helps seal small exhaust leaks even on cars that have 1 or 2 missing studs they claim.

I just got it in but have not installed it to determine if it fixes my leak. But by the look of the design and quality it seems like it has a good chance.

If you were able to get the tap out then now the easiest thing to do would be drill it and tap it for a helicoil insert. I was able to get one broken stud out and followed the "How to use a Helicoil" thread. It was very simple and I had no previous experience with them before, but still finished in about 30 mins. After it is helicoiled, you just take your new m10 exhaust stud and thread it in nice and easy just like it never happened.


This is an easier option than tapping for a larger stud also because you will not have to worry about drilling out your exhaust manifold flange to fit the bigger stud.

I think if you do a nice Helicoil job and use that gasket you will have no leaks and not have to worry about it for a while.


FFWD Connection - Race Injuns That Will Freeze Your Brain
 
Well, I just went as far as drilling a hole for an M12 and there is still an area where it won't seal (meaning there is a small area below the hole remaining where the dremel made its own whole. Is that stud under pressure? Could I just get an M12 stud in there put RTV in there and call it a day or will I have problems...don't want to chance M14.

What kind of pressure is there and can RTV make up for the open areas or??
 
Well, I just went as far as drilling a hole for an M12 and there is still an area where it won't seal (meaning there is a small area below the hole remaining where the dremel made its own whole. Is that stud under pressure? Could I just get an M12 stud in there put RTV in there and call it a day or will I have problems...don't want to chance M14.

What kind of pressure is there and can RTV make up for the open areas or??

It isn't a pressurized oil passage, but there will be crankcase pressure in there. You can try rtv, but i can't guarantee that it will work. At this point i would seriously consider pulling the head, and having the hole welded shut than re drill it.
 
It isn't a pressurized oil passage, but there will be crankcase pressure in there. You can try rtv, but i can't guarantee that it will work. At this point i would seriously consider pulling the head, and having the hole welded shut than re drill it.

Gotcha, this is what I am talking about BTW since my camera is crap.

The red circle represents the hole, and the black area represents the areas that I went too far wit when I used the dremel.

To be honest, the below is a bit of an exaggeration but wanted you all to understand.

An M14 hole will most certainly take care of this.....I don't mind drilling the 4 layer gasket and the exhaust manifold.

The thing is, do they make M14 studs like this.
 

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Me and my friends spyder had a similar problem we ended up pulling the head head a few stripped bolts, and had our welder retap them and install studs in the head, he didnt want to but he didnt have much choices due to his time and space constraints.
 
Me and my friends spyder had a similar problem we ended up pulling the head head a few stripped bolts, and had our welder retap them and install studs in the head, he didnt want to but he didnt have much choices due to his time and space constraints.

Well, I will call this complete.

I drilled a 13/32 hole for a M12x1.75 tap.

The bottom of the dremel holes as illustrated above were still present (but really nothing nearly as severe as the pic ).

I decided to tap it.

This time around I took my tap and put the cutting oil on it. I held it straight and true and took my time.

I had the valve cover off so I could see everything going on and didn't come remotely close to bottoming the tap out THIS TIME.

I took a look at the threads the tap created. The threads came out great with only some slight evidence of galling. The threads look like there are some minor nicks in them at this point. I am definitely comfortable with putting RTV (the right stuff unless you all know of something better) in there and calling it a day.

So I have metal shavings to deal with. I'll use some more break clean then dump some oil down the drain area and use some cheap oil and filter. I'll change the oil quickly again and be done with this.

Advance Auto sells 12x1.75 head studs so I am fortunate.

I'll have to enlarge one hole on the exhaust manifold and the 4 layer exhaust gasket slightly.

I'll clean up all the surfaces, copper spray it all up and be done with this.

Thanks for all of your support, your help was overwhelming. :)
 
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