Broken bolt

mdh157

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All,
I was working on my Ambassador and one of the bolts on the gooseneck broke off. I tried everything to free it including left handed bits but all i am doing is breaking bits. Have broken 6 already and cannot get deep enough to try to get an extraction bit on it. Any ideas? Welding is not an option.

Take the manifold off and i might as well just get another manifold bec i still dont see how it can be removed without damaging the threads.

Lot of work for a thermostat.
 
All,
I was working on my Ambassador and one of the bolts on the gooseneck broke off. I tried everything to free it including left handed bits but all i am doing is breaking bits. Have broken 6 already and cannot get deep enough to try to get an extraction bit on it. Any ideas? Welding is not an option.

Take the manifold off and i might as well just get another manifold bec i still dont see how it can be removed without damaging the threads.

Lot of work for a thermostat.

OK, you've struggled enough. Left handed drills work sometimes... Extractors hardly ever work and usually make things worse when they break off. I would just drill it out and Heli-Coil it (if needed) at this point, but if you are ready to pull the manifold anyway, take it to a good automotive machine shop. They'll take care of it.

BTW, damaged threads are an easy fix with a Heli-Coil. The end result will be stronger (if done correctly) than the original threads.
 
Kroil penetrating oil before you start next time but in this case what John said.
 
Well the first thing i nred right now is a bit that will drill it out. Nothing is going through no matter what, its like i am using a butter knife.
 
Well the first thing i nred right now is a bit that will drill it out. Nothing is going through no matter what, its like i am using a butter knife.
You did get the broken drills out, correct?

Is it broken off flush? Since you've been trying to drill it out, is your drilled hole close to center?

It's probably a 5/16 -18 thread and if you were right in the center, you can kind of sneak up on the size. A 3/16 drill first... Ideally. a letter F size drill (.257") will drill the bolt out leaving just the threads... But that's doubtful. So... if you get up to 1/4" you've pretty much drilled the bolt out.

But! The final result might have to be a Heli-Coil and for that, you'll need the proper size drill (sometimes included in the kit) along with the tap and inserts. About this time, your investment might hit the "take it to the shop" price. Just saying...
 
One of the real small bits is still stuck in there. Yes, broken off flush and hole is close to center. Later today I am gonna pick up a carbide tip bit set bec the titanium coated tips will not drill through it.

BTW John, I do not like the idea of "take it to the shop" price!!
 
Those “easy outs” are an oxymoron. They are not easy and they never come out. I used a center punch to break more of the broken bit to deepen the divot, then oiled it up and used a larger bit on slow speed. Step up slowly with larger and larger bits until you can get the right heli-coil tap in.
 
One of the real small bits is still stuck in there. Yes, broken off flush and hole is close to center. Later today I am gonna pick up a carbide tip bit set bec the titanium coated tips will not drill through it.

BTW John, I do not like the idea of "take it to the shop" price!!

First, the TiN coated drills aren't any harder than your regular HSS drills. It's a wear coating and that's it. Under the coating is a drill made from High Speed Steel (HSS).

Since you broke a drill in there, that TiN coat drill isn't going to do anything except get dull in a hurry. The carbide tipped drill should cut into it, but carbide is very brittle. It's also not going to want to "follow" the hole because of the broken drill. You do have to go to a slightly larger drill than what is broken too. Trying to do this with an electric drill is going to be tough.

You don't want to pay the shop price, but a good single carbide tipped drill would be $15 or so and you're probably going to chip the edge on at least one. A "set" is going to be expensive. Masonry bits aren't going to cut it (pun intended) if that's what you are thinking.

I hate to pull money out of my pocket too... But it happens. Everyone breaks a bolt now and again. Breaking the drill off complicates things a ton. Break the carbide drill off and you're screwed. Got a friend with a welder? Welding a nut on it might be the perfect solution, even if you have to take the manifold to them.
 
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I broke yet another bit last night.........must be moving toward some sort of record. Am gonna poke a bit more before I succumb to removing the manifold bec there is so much work to put all this back together.
 
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You need a Oxy-Acetylene torch, heat up the area red hot to take the hardness of what ever bits you have in there. Start right in the center till the bit/bolt and surrounding area about the size of a quarter is red hot or 'Cherry Red' as some in the welding industry refer too. Let it cool slowly by just the air, don't dump any water out on it. Center punch it as best you can in the center of the hole, then with a normal drill, drill it out, be careful about drill wobble and wander, if you encounter that right off the bat, remove manifold and clamp it in a drill press (make sure it's perpendicular) and carefully drill it out with many small cuts (presses).

If the hole gets to big for a heli-coil you can drill it out larger and put a steel insert in or get another manifold.

(edit) If your uncomfortable with torches or heating metal or setting fire to a dirty greasy engine, hire someone to do it. Quit beating yourself up over it, I don't know what you do for a living, but what is your free time (after a 40hr week) worth? I can remember a Lawyer complaining about a bill, whats his free time worth? You know after 40 hours is overtime? I think Lawyers were billing about $100 an hour back then.

.
 
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time to pull the intake and replace it with a new one. by the time you are done damaging the surface your stat housing is not likely to mate properly and you will have a coolant leak from the stat housing where it meets the manifold. a new aluminum intake is likely around 200 bucks.
 
Agreed @livininharrow . After all consideration I have decided to pull it. All loosened up but i am gonna put a factory 4b intake on it so now i am gonna look for one of those. As usual, have found one but nowhere near me. I will repl the intake, prob put an Eddy 4 w/elec choke on it and dual exhaust. that should give me a few more horses without costing a kings ransom.
 
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