Drilling out broken stud

[kelsham]

Which would be the best type/make of drill to attack a broken stud in my Jaguar XJS manifold. I am going to attempt it from below the car, removing the manifold is a major job.

Regards Kels.

 

[rkde]

sometimes it is easier to weld a nut on the end of the stud, just to throw another option in the pot

 

[steveo3002]

yeah id try and weld it if at all possible

get a good slug onto a nice fitting large washer ...then tack a nut to the washer

 

[Robotstar5]

and the heat of welding can break the rust/corrosion holding it in too

 

[chunkolini]

After welding it is it best to try and remove it hot or let it cool down and allow the bolt to contract as it cools?
My guess is to go and have a cuppa and let it cool down.

 

[Sean]

while hot i usually give it a good "wake up call" with the ball pein then get the spanner on it quick

 

[pedrobedro]

Check they are ordinary steel before you try to weld to them, if they are stainless studs they turn into chocolate and break off even easier and are impossible to drill out as they work harden. If they are ordinary then you can drill them with HSS drills and tap the hole to get what is left out of the threads. I had to weld to the heads of some rounded caliper bolts a couple of weeks ago and they were flying out hot and started binding as they cooled down but it was thread lock setting as it cooled.

 

[langy]

They won't be stainless on an XJ6, I have to do this all the time, just centre punch it and drill using a Dormer A002 drill and gradually open it up.

 

[cecotto479]

My preferred method where possible is to cut a slot across the stud with a 1mm disc or hacksaw and get some heat into the tapped bit and then wind the broken stud out with a screwdriver.

 

[langy]

My preferred method where possible is to cut a slot across the stud with a 1mm disc or hacksaw and get some heat into the tapped bit and then wind the broken stud out with a screwdriver.

I wish i had your luck mate

 

[kelsham]

Thanks for the advice. The stud broke as I tried to remove it with a stud extractor, there is limited access, it is an XJS vee twelve.

I can use the extra holes Jaguar tapped in the manifold and rotate the locking collars. Then the brackets for the heat shield will be in the wrong place.

I will try drilling in preference to welding, when I tried a drill on a piece of the broken stud it seemed unwilling to cooperate.

Hence the question, I was hoping for a magic drill bit.

With better access I would probably try welding. As it stands I will have to introduce the drill from above and then reach up and operate it from under the car.

Hot droplets of metal down my sleeve would probable feature in my future were I to try and weld it.

If this fails I will have to make new brackets, just trying to keep it standard.

Regards Kels.

 

[Robotstar5]

Hot droplets of metal down my sleeve would probable feature in my future were I to try and weld it.

That's why you wear welding gauntlets duct taping your sleeves at the wrist can help

 

[langy]

Thanks for the advice. The stud broke as I tried to remove it with a stud extractor, there is limited access, it is an XJS vee twelve.

I can use the extra holes Jaguar tapped in the manifold and rotate the locking collars. Then the brackets for the heat shield will be in the wrong place.

I will try drilling in preference to welding, when I tried a drill on a piece of the broken stud it seemed unwilling to cooperate.

Hence the question, I was hoping for a magic drill bit.

With better access I would probably try welding. As it stands I will have to introduce the drill from above and then reach up and operate it from under the car.

Hot droplets of metal down my sleeve would probable feature in my future were I to try and weld it.

If this fails I will have to make new brackets, just trying to keep it standard.

Regards Kels.

Thats why you need decent quality drills like the Dormer A002

 

[TAITSIE]

I wish i had your luck mate

Me too
Had to drill out some broken studs on a Defender water pump last week

 

[kelsham]

I wear glasses for close up work, I would be lying under the car with the helmet restricting vision, arm up into the engine bay.

I have already moved the steering rack just to get sufficient clearance to reach up with the stud extractor. I would have to weld at arms length, I am just not up to it.

Looks like Mr Dormer will be profitting from me.

As a point of interest two of the studs snapped off where they passed through the flange connector ring. I had been too clever and heated the nuts with a small gas blowlamp.
Looking back it seems as if the heat expanded the stud into the manfold there by tightening it. Because the heat failed to break the bond on the long nuts Jaguar fits, they are made of steel, the bolt gave at the end of the nuts.

I later removed both with a stud extractor. Sadly the one still in the manifold actually unwound the nut. but galled the thread. The extractor broke it off flush with the manifold.

SNG Barrat supply replacement studs and nuts, the nuts are brass, much more sensible.

Regards Kels.