FAQ : Technical - Install Issues

I broke a stud off when removing my exhaust manifold. It broke above the surface of the head, what is the easiest way to get it out?

These two questions can be answered together as the process for removing the studs is basically the same aside from one advantage of having the stud break above the surface of the head. We'll tackle that first.

If your stud is broken above the surface of the head, you have a very good chance of removing it without any damage to the threads in the head, assuming you have access to a welder. With a welder, you can weld on a hex nut which can then be used to remove the rest of the broken stud. The high heat from the welder will also help free the stud so work quickly. Worst case, the stud breaks again and you just move on to the next steps.

Assuming your stud has broken below the surface of the head, or flush with it, you are left with two options, both requiring some skill and/or specialized tools. The first is the EZ out. Available on our website, EZ outs utitlize a left hand spiral which, when turned counter-clockwise, digs into the stud (after drilling the appropriate size and depth hole) and then attempts to turn it out of the threaded hole. EZ outs can be difficult though. First off, they work best with heat. If you have a torch (propane, acetylene) you can use it to help heat and expand the aluminum to help free the stud. Once the aluminum is hot, insert the EZ out and try to free the stud. Be careful though, because as strong as EZ outs are, they will break. And when they break they leave an extremely hard piece of steel in the center of your threaded hole. An ordinary drill bit will not even touch the hardened steel of an EZ out. You'll need a carbide bit to drill out the remains and then you can proceed to the next step.

The second option for a flush broken stud is the drill and tap method. For this, you will need a set of drill bits starting around 1/8" and increasing in small steps up to the correct drill size for tapping an M8 hole (marked on the tap itself usually). First, use a center punch and hammer to make a point in the center of the stud. If your first attempt is off center, you can use the punch at an angle to "push" the hole more towards the center. Once you have a good mark, use your smallest drill and drill through the stud making sure to not go see deep as to bottom in the aluminum head. you can use tape around your bit to make sure you only go just as deep as the end of the stud (measure and mark with a removed stud). Check to make sure this hole is as centered as possible. If it's close, continue on with the next size until you reach the tap drill size. At this point, the leftover pieces of the stud will either come out with the drill bit or fall right out. If not, enough threads are usually exposed to allow starting the M8 tap and running it down through the hole to clean up the threads. If the tap starts to get stuck, back it out a turn and then back in. After you get a few turns in, back the tap all the way out and clean out the metal bits. Go in a little further and then repeat. Do this until you have enough threads cleaned to install a stud.

Now, if your hole is not centered, you can try and use a rotary tool and some grinding bits to create a centered hole. Do NOT try and angle a drill bit in there to "move" the hole. Chances are, you'll end up breaking the drill bit and not changing the hole at all. Once you are satisfied with the hole center, start the drilling process again.

Worst case with the drill and tap method is that you are unsuccesful and do some damage to the threads. If so, continue on to the next question.

The threads in my head are damaged, how can I fix them?

Fixing damaged threads can be as simple as using a tap to "clean up" the threads in the head if, for example, they were crossthreaded. This however is not usually the case. If in an attempt to drill out a broken stud you destroyed the threads in the head, the head is still useable. You will need a thread insert kit like a Helicoil kit. The Helicoil kits are readily available (also through our website) and contain a drill bit, a special tap, a few coiled inserts, and a special installation tool. You drill out the hole in the head using the provided drill, tap the hole, then install the insert and you're done. This can be done with the head in the car which is quite useful for those not wishing to do a headgasket. The only caution you need to take during this prodcedure is to drill straight and only as deep as the previous hole. The aluminum is very soft and won't take much force to cut. If you are concerned about drilling too deep, stop and check often.