Jimmy71

Trying to get the word out about the best way to fix those inconvenient broken exhaust manifold bolts that can't be removed. I work in a shop and use the K.A.P. exhaust manifold bolt repair kits and have had great outcomes with them. Super easy to install and save time and money. I know a lot of people struggle with them, so I figured i'd spread the word about them because they truly are worth a look.

tech2

if you have access to a mig welder; weld a nut onto the broken stud. this will work even for studs broken below the surface of the head. 1.5hrs per side start to finish. I've never had a stud I couldn't get out with this method; and its done right.

jordy

I have used these and 100% agree and would recommend. My mechanic wanted nearly $1,000 to drill out the bolts and replace them. The brackets were way more affordable and way more durable than new bolts. Plus, I could fix it myself which saves on labor costs. Make sure you are looking for the kral auto parts brackets when looking into it. There are some knock-offs out there that are not good quality.

Gumby22

In my experience, the brackets are fine when it’s not worth going after 1 broken bolt/stud, or as a temporary fix if you need to get by until a proper repair can be done. The drawback to them is depending on where the broken bolt is, you can’t install it (for example, the front left cylinder head is usually blocked by the bracket for the alternator and power steering).

I agree with tech2 in that welding a nut onto the stud is the most effective method. In some cases I’ve welded a nut onto the stud and then welded a larger nut to the smaller one to get more leverage on them. This also heats the stud and eliminates the need for a torch.

The only extra step I also take is as soon as I’m finished welding (before the red glow fades) I will touch a tire crayon to the base of the stud at the head - the wax melts and wicks down into the threads like solder, lubricating it and making removal even easier. Even if you just heat the stud with a torch (it has to be red hot) and use the tire crayon, this works well enough that sometimes all you need to remove it is a pair of pliers.

tech2

interesting...i will try the tire crayon

Gumby22

Toilet gaskets work too. The first time I learned about the wax, my dad was helping me remove a broken intake bolt from the head on my 91 F150 (their 5.8 engines were notorious for the lower intake bolts breaking off). There was barely enough of the bolt sticking out to get a grip on it with needle nose pliers. My dad had read an article about the wax method in popular mechanics, so we decided to give it a try, but the only thing in my dad’s garage was a toilet flange gasket (not used, thankfully ).

While I was at the ready with a screwdriver that had a glob of wax on tip, my dad used the brazing tip to focus the [acetylene] torch flame only on the bolt. Once it was glowing red hot, I touched the wax to it - we were able to get the bolt to turn a little but it still had quite a bit of drag to it, so we heat it again, and then one more time after that and that was enough to get it out. I’ve kept that method in my “mental toolbox” ever since.

Since I started servicing cars professionally, tire crayons seem to work just as well, but I keep meaning to pick up some cheap candles or hobby wax, just to see if one works better.

repairman54

I'm a fan of Kroil . Let it soak some before trying. Best spray on I've used, beats PB by a mile. Wax is my last resort but usually I've past the point of no return by then LOL.