Broken exhaust manifold bolts

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Magnum87

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I have a 5.9 mag that’s not in a vehicle. Any tips on how to remove these 2 exhaust manifold bolts that are broken? Motor was clean only 50,000 miles. So they were not all rusted up etc.... don’t know why they broke. Was like this when I got it. The one is broke off almost flush and the other one is broke off up in the threads pretty far. Thanks

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I would suggest left-hand drill bits, and easy out.
Failing that i have used a torx bit and a slightly smaller drill bit.
 
I would start with a small reverse drill bit and work my way to bigger ones trying not to hit the threads...
Harbor Freight sales them...
 
Common with those.... and a pain. Heat and a grip pliers may work. If not, drill starting small.
 
I’ve welded nuts onto broken studs in aluminum heads, then twist right out. I can’t tell if your heads are aluminum though, look like iron.
 
First thing is plenty of PB Blaster and let soak. One looks fairly easy and the other a bit tricky!
 
Yup, what post #6 said. That's your best bet. Get a nut and place it on the head right over the hole and mig weld it to what's left of the stud. That one that's broken off deep is gonna be the trick. It's gonna be a challenge to build up weld without involving the threads in the cylinder head. Someone really good with a mig can do it. The drill bits and ease outs are a recipe for disaster there, IMO, as those studs are likely in there TIGHT. What will happen is, you will end up breaking a drill bit off in a stud OR breaking an ease out off in a stud. THEN you will have "fixed it so it caint be fixed" because drill bits and ease outs are WAY hard and will be all but impossible to drill out.
 
Just a thought, is the one broken off deep still have enough threads to just use a shorter bolt and just leave it there?
 
The deep broken one, i have used a bolt i drilled down the center,as a guide.
 
I had one in a BB 906 head that snapped the easy out on extraction. Got cocky and What a pain that was. I usually step drill to almost thread and they come out fairly easily. That one I ended up knocking into the water passage and it came out through one of freeze plug holes. Had to put a heli coil in that one with lots of thread locker. Re chased afterwards and all good.
 
In other words always have patience. After two Easy ones, I f’d up and short cutted!
 
If the studs are sticking out from the manifold surface you can heat the head and see if a quality Vice Grip type plier will take them out. If they are below the surface, welding a nut onto them can extract them. If they are buried (like I see in one of your photos, You need to drill them out. Carefully start with a small bit 1/8" and keep drilling bigger. You can try a easy out (I prefer straight splined types with the proper sized drill bit) Remember, if you break off a drill bit or a easy out you are pretty much screwed. I have used carbide tipped masonry bits with limited success.
 
Ok thanks guys! I don’t have a mig. And don’t know how to use one. Maybe I can get a shop to do it for me or find someone who can stop by. The motor is out so if I have to haul it to a shop guess I can do that also. Looks like the mig would be my best bet.
 
If they are in cast and sticking out i use my air hammer and water. A little vibration and water breaks up the rust scale. Will not work if it had oil sprayed on it first.
 
Torx, modified because it was in deep. Ford van behind coil spring tower. Want a challenge? I wont tell you how long it took. Yours is a cake walk...
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Good luck. I have one just like that sitting in the shop. I let it soak in penetrating oil for a couple weeks then drilled it out to almost the threads with left hand drills. It is still soaking and still will not come out with easy outs. May try the torx trick.
 
My son and many good machine shops with brains Tig weld them out.

Build a ball up on the stud once you can grab it with something cool it with air. Screw them out with your fingers. There are several heads on a pallet in the shop right now that have to be done if I am there I will video it for you all. Cooling the stud after heat from building it up shrinks it .

Most thread right out with your finger. I have seen him having to use a vice grip or weld a nut on the ball rarely. The weld does not stick to the Cast or Aluminum. Never drill them at all anymore he even does it when guys bring their cars here on trailers with the manifold off. He bought a real short end for the tungsten. Easy outs are barely used anymore at good machine shops once they have the Knowledge. Some of the things he shows me I can't believe myself until I see him do it.

Remember when you weld on the stud the current goes from the head through the the corrosion and into the stud. The corrosion turns to Powder. Cooling it shrinks the stud and Wah Lah. it come right out.

There is a head here with a thread insert in it. and one with a drill bit broke at an angle. Those heads will get filled and resurfaced and then drilled and rethreaded. Triple the cost once you try and drill it and screw up.

Old guys like me should throw the easy outs in the trash. LOL This boy is teaching me things everyday and its aggravating at times when he shows me the new ways. I am used to teaching him. But he is not always right. I still get him once in a while. LOL
 
If the bolts that broke are on the ends of the head, the hole goes all the way through. So it might be easier to screw the broken piece into the head and get it out with a magnet??
 
My son and many good machine shops with brains Tig weld them out.

Build a ball up on the stud once you can grab it with something cool it with air. Screw them out with your fingers. There are several heads on a pallet in the shop right now that have to be done if I am there I will video it for you all. Cooling the stud after heat from building it up shrinks it .

Most thread right out with your finger. I have seen him having to use a vice grip or weld a nut on the ball rarely. The weld does not stick to the Cast or Aluminum. Never drill them at all anymore he even does it when guys bring their cars here on trailers with the manifold off. He bought a real short end for the tungsten. Easy outs are barely used anymore at good machine shops once they have the Knowledge. Some of the things he shows me I can't believe myself until I see him do it.

Remember when you weld on the stud the current goes from the head through the the corrosion and into the stud. The corrosion turns to Powder. Cooling it shrinks the stud and Wah Lah. it come right out.

There is a head here with a thread insert in it. and one with a drill bit broke at an angle. Those heads will get filled and resurfaced and then drilled and rethreaded. Triple the cost once you try and drill it and screw up.

Old guys like me should throw the easy outs in the trash. LOL This boy is teaching me things everyday and its aggravating at times when he shows me the new ways. I am used to teaching him. But he is not always right. I still get him once in a while. LOL
Right on. 5.4 liter Fords are noted for exhaust studs rusting and breaking. There is a local guy with a small portable tig that does just what you described. He has extracted hundreds that way. You could probably clamp the head to the Bridgeport and machine it out with a carbide end mill as well.
 
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