Broken exhaust header bolt

Yesterday I noticed a small exhaust leak while riding the XJ around. When I got home, I came to find out that the bolt on my #4 exhaust header was snapped clean off (bolt and flange nut gone). How do I go about removing what's left of the bolt?

 

bigfitz has a link in several posts for a chemical that dissolves the steel but leaves the aluminum. This might be a good application for that.

 

Save you some digging; both literally (in your cylinder head) and figuratively (on the site) http://www.chemical-supermarket.com/pro ... ductid=574

Thanks, IWGO, and I mean that.

 

If you do use this stuff... report in with how it works.

 

Anyone have experience using an "ez-out" on something like this? I don't really want to invest in the chemical since I probably won't be using it very often.

 

There are a couple of threads running right now from folks who now have a broken EZ out or drill bit stuck in their head.

You can give it a try; the problem is that the aluminum is SO soft compared to the stud. The best practice is to pull the head, take it to a machine shop and have them remove it, usually by "burning" it out with their EDM.

If you're going to attempt drilling it and extracting, then soak it in Kroil for about three days beforehand.

 

Broken studs are really a pain. If you are super good with a center punch and a drill you can drill it out to the point where a tap will clean out the threads. BUT most of us (including myself) are not good and get off center and make a mess out to the who;e thing. My vote is to dissolve it or pull the head and go let a professional do it. Good luck either way you go

 

So I'm planning on attempting to remove this bolt myself in the next few days. I read other posts, and people were mentioning to use kroil to soak all the nuts and bolts before attempting to remove them. I'm unable to get any kroil locally, so I was wondering if pb blaster would be sufficient if I sprayed it all down for a few days before attempting removal.

 

All I can tell you is that Kroil works when PB Blaster won't.

That was on heavily rusted parts (rusted-in fork caps) I can't say for sure in this instance. But Kroil worked when nothing else did, and I used to swear by PB Blaster.

HEAT is actually going to do you the most good, if you can just start a hole in the center of the stub enough to get a bite with something and then heat the area, it'll likely turn right out.

If it was me, I'd try dissolving it first. Yes, the stuff's kind of expensive, but it' a lot cheaper than a head gasket plus whatever you'd have to pay to fix it after you chew it up.

 

Thanks for the input guys. I ordered some kroil on amazon, and I plan on soaking ALL of the nuts and bolts (exhaust gaskets are being replaced so they must all come out). I'll then heat it up with a torch and HOPEFULLY drill it out. I'm planning to extract it next weekend. Wish me luck, and I'll give ya'll an update on how it goes.

 

the route I usually take for this problem.

1. Center punch, BE AS EXACT AS YOU CAN. If you get it wrong you can use the tip of a round grinding stone to preflatten the area for a good punch.

2. Small drill bit. Be careful to follow your punch, and drill as straight as possible, use oil, take your time, dont break the bit (happens more often than not as you break through the backside of the bolt into clean air or the soft aluminum behind it. avoid that.

3. drill for the easy out. Determine the best easy out size and following your pilot hole drill the hole out to the recommended size for that easy out.

4. bite and heat and oil. soak the area with the penetrant of your choosing. Carefully start the easy out, than once it starts to bite heat the surrounding area thoroughly with a propane torch and apply even steady pressure to the easy out. Dont FORCE IT and break it off like most people do. Let the heat do the job. It shouldnt require more than about 8-10ftlbs of torque. (about the amount of torque you can get by hand on a screwdriver).

5. plan b. If that fails STOP. breaking off the easy out will compound your problems. instead simply continute expanding the hole with each step of your drill bits (should be in 64th's), until you can just see the edges of the original threads.

6. retap. be careful you get the tap started in the old threads then turn it in, stoping and backing out after every 2 full revolutions to make sure you are still on the threads and to remove the chips.

 

If you aren't experienced with removing broken studs, find someone who is. This is one of those deals where you only have one shot and getting it right the first time is a must. Check around and see if you can find your towns' "old codger machinist", seems like every town has one....and talk real nice to him and he just might let you pay him to do it. I got into a jam a couple years ago and found the "dad" of Colemans speed shop, a local go-fast car place....turned out the old man still did work on the side....he was about 85 but absolutely had more knowledge then I'll ever have. His home shop made me drool.....and he helped me out....start searching.

don't mean to hijack but.....

Fitz, or anyone else,

Can anyone vouch for thechemical solution? Yes, it's expensive but I don't mind paying the price to have it in my shop if it REALLY works....and by that I mean within my expected lifetime<LOL>.....so, does anyone have first hand experience with it?

jeff