Removing the head pipes to replace the exhaust on my 65. Got all bolts to come out of the manifold except one was broken off in the manifold. What is the best way to remove the Broken stud from the manifold? Thank you.

 

Is there any length of the bolt sticking out to grab on to, or is it broken flush?

 

Seems to be broken flush

 

Drill and easyout, weld a nut and remove, drill and install helicoil, your choices and pain are endless.

 

When drilling take time to be certain it is being drilled on center. Even the slightest amount off center causes problems.

Have had success by grinding the broken stud flat, using a center punch to make a starting point for the drill, drilling out as much of the center of the bolt as possible without contacting the threads and then collapsing the remains/sleeve inward from the threads with a pointed punch.

 

Good thing you are taking the head off. Eric has your answers but IMO try welding the nut first as the heat cool cycle will help loosen it. There are some good videos on some of the TIG welding sites on how to do this procedure properly. If that doesn't work (it should), then
Go with the EZ out. Absolutely make certain you use a good quality tool and whatever you do don't break the EZ out in the predrilled hole. They a difficult t drill out because they are hardened which also makes them brittle and prone to breaking. Failing that as well, it's time for the heli coil.

 

Amen. EZ-Outs are apparently made out of hardened diamond.

I had a similar situation and did break the EZ-Out. After spending way too much time trying to fix this mess, I ended up having a local machine shop use 'EDM' (Electro-Discharge Machining?). Whatever this magical process was (I didn't see it), they 'burned' out everything in the hole and left the threads perfect & charged me like $25.

 

Never heard of that one sounds like an excellent way to spend $25!

 

I have had good luck with just drilling and then run a tap through the hole... Just be sure you drill as close to center of the broken bolt as possible.... I have also drilled close to the thread size, normally using a drill just a little smaller then the actual tap drill size, and then remove the rest of the metal away from the thread area with a point chisel and then run a tap through....

 

Weld a washer to the broken bolt, then weld a nut to the washer. Not only does this give you something to wrench on; it also puts a lot of heat to the broken bolt which helps loosen it. You might have to do it several times before it breaks loose, but it works almost every time.

 

Welding a nut on is the industry standard ... providing you have a welder. A cheap stick welder will do the job. There are even special electrodes for bolts broken off below the surface, like Cronatron 333 and Super Missile. Their flux coating keeps the electrode from sticking to the threads. EDM is fantastic, but you''re not gonna do it in the driveway. And always make sure your local machine shop actually has one before you go pulling heads and taking them for a drive ... although even without one, the machine shop should be ready for this type of job.