Hi there!

A slight mishap. 27 years ago the manifolds got new studs. One decided to snap off whilst trying to replace it... Result: flush with exhaust manifold. Nice and straight. Anyone got any tips how it would be best to remove it? I would use the other holes but I NEED to use this one stud to fit the PAS pipe heatshield...

Any ideas? I can't get the stiltsons on, as the stud doesn't have any grab area. I'm trying to soak it but I doubt it'll work well enough. Drill it out? Possibly damage the thread...

Or would it be easier to simply purchase a used one? Rear left side in case someone has one

Cheers

Damien

PS: my engine is now officially clean!!! All gunk gone

 

I have in the past mig welded a nut onto what's left of the stud the heat also part of the job. but it would mean removing the Manifold. But as you are probably going to have to remove it to do anything properly that's the way I would go.

 

Manifolds are out still as the engine is out...

No rests grabable. So no chance of welding onto it

 

Happens to me nearly every week in the machine shop. They sell a tool called an Easyout where u use a left hand thread drill and drill a small pilot hole with drill in reverse. Sometimes it comes out with just the drill. If not you use the Easy out tool to grab the bolt. They come in a variety of sizes.

 

^ This

There are numerous ways of removing stuff like this, you start at the easiest and work your way down to the biggest paint.

Right now the best thing would be a pilot hole and extractor. The size is very important. Hole too big or small means the extractor won't grab, extractor too small mean it will break off. Try that out before trying to drill it out completely.

Question: If the bolt is broken off, why can't you remove the manifold, giving you the cm or whatever shoulder of the stud exposed to try and remove with vice grips or an extractor tool?

 

If all else fails bring it to machine shop and have them remove it. They probably won't charge much

 

It is a stud IN the manifold between manifold and downpipe. It has sheared off flush with the surface of the manifold... The manifolds are removed from the engine... A Fee thread down is another called 'Sandblasted headers, spray...' -would be awkward sandblasting them on the engine in site

 

Ahh gotcha, I thought you meant in the head.

 

Hi Daim

If its the Stud between the Manifold and the Downpipe.

I had a similar situation when a Calliper Bolt broke off Flush and there was nothing to get the Mole Grips on.

So what I did was drill right through the Bolt and then try and unscrew it with an 'easy out' which in this case didn't work, as it expanded the Bolt that I drilled through and if anything made it grip tighter.

Plan 'B' was to drill a bigger hole right through the Bolt as close to the Thread as I dare, then I very carefully sawed through the wall of what was left of the Bolt with a very small Hacksaw, until I could feel the Hacksaw Blade just touching the Thread.

I didn't just cut through the wall in one place but in four different places around the hole that I drilled, which was a very painstaking PIA Job.

But maybe easier for you, as you have the Manifold off. (I had to do this in situ)

Then using a very small 'dot punch' and a small hammer, I managed to get the 'dot punch' to dig in to what was left of the Wall and very carefully hammered away until the Wall with all the Hacksaw cuts in, came away from the Thread and started to collapse upon itself.

At which point I could manage to get what was left of it out of the Hole using some Long Nose Pliers, which left the Thread undamaged.

It took all day to do it but as you've got the Manifold off, it might be quicker for you.

It was a Total PIA but there really wasn't any other way that I could find to do this job.

 

Daim
The manifold cast iron will be quite brittle with age and heat cycling. Go about it very slowly and carefully with lots of lubrication. For a start, before you embark on OB's sensible system, soak the piece in 50/50 acetone and ATF mix for about 3 days. After than once you start drilling it may just chase the broken piece out.
Greg

 

I second 86jag and the easyout method. I used these numerous times when I was renovating my car.

The easyouts I have are used in a drill in reverse as they have their own center drill to start the process

 

My manifolds have 2 studs and 2 treaded holes as spares. Which I used when I broke a stud off. Does yours only have 2?

 

Yeah, an easyout or screw extractor kit is a great tool to have in the garage. I had to use one on my tranny pan drain plug that I stripped when I over torqued it.

If the stud is a high grade bolt and difficult to drill the pilot hole, maybe you could weld or JB-weld a dollop on the top of the stud, then drill the pilot hole on to that.

Also, since it stripped while extracting, chances are it's siezed. In which case, I recommend the old melted wax trick: https://www.jaguarforums.com/forum/x...2/#post1482053 This might work after you get the pilot hole in.

Padre

 

Mine have 4 too BUT I need to use this hole to fit the heat shielf for the power steering pipes...

 

Well? Does your MOT bloke know what the studs they should be on¿ buy the way. Only fit helicoil nuts on the new studs. Only avail from jags. (I think) they will not snap off you crap old studs 4 sure

 

EZY out is plan Z in my experience!!! I've busted more than a few in other critters, but similar issues.


On the bench is a huge advantage.


Having the busted fastener flush is good.!!


Very carefully and with a very sharp small drill go to daylight
Follow with a larger. lots of oil to keep the work cool .


Now, if not yet successful, the remnant of the busted fastener is
thin.


Use a thin and very sharp chisel to peel out the remaining shell.


Chase the threads and voila New and ready to go threads!!!


Caveat: Sharp bits, lube and pressure. Do not work harden the
busted fastener!!


Carl

 

I have also tried heating up the bolt with a torch. The difference in temperature expansion helps break it free.

Good luck!!

 

You just need it for the shield? Why not weld a threaded rod on?

 

If you do use the extractor be very careful not to break >it< off in the stud - they are very hard and having it stuck in there will greatly reduce your options - a drill bit won't make a dent in those things. I wouldn't use one unless the stud is already sort of loose and you just can't get a grip on it.

Drilling the stud out would probably be my first choice if it is really solidly stuck. Not really as hard as it might seem... It sounds like the broken off surface is pretty flat? Good if it is, first step is use a center punch to make a good starting "dimple", as centered as you can on the top. Then start with a pretty small drill bit, use plenty of oil (something like thread cutting oil best, available in hardware stores here), go slow and keep as straight and centered as you can. Then repeat with gradually larger bits, going slowly, look through the hole as it gets larger, you should be able to see when the root of the threads are about to break through before any damage would occur to the manifold. Once you can see those threads (may be only on one side of the hole though) you can try to peel the remains of the stud out with a small dental pick type tool, or what ever similar you have. If you still need to remove more but think the drill will go too far you can finish up with a round file or tiny grinding wheel. The main thing is to just take your time and keep everything as straight and centered as you can, increase size gradually, and keep checking to see how close you are.

Hope this helps, and good luck!

Eric