Advice on removal of snapped exhaust studs in head

[votivequagmire]

Hi all
I have two exhaust studs snapped flush with the head on my M20.
I would appreciate any and all advice which will aid me in the removal and replacement of said studs please.

Thanks in advance.

[e30maddog]

ouch!! looks like you are gonna have to drill it out m8. or if you have a welder you could try to weld the inside of a nut to the stud and try to turn it out. if not just take a small drill bit to the stud center take it about 5mm deep then go at it with a stud remover (the drill bit looking one) and turn it out, although ive never had much luck with the drill bit style stud removers but it might work out.

[johnt0709]

Hope this helps - someone with the same problem - try a search in technical help
http://www.e30zone.net/modules.php?name ... ud+snapped

[Ajsingh]

Take it to a machine shop, someone who does skimming and so on. They will take it out for you, as they have all the tools and makes its easy for you

[leeparkes]

Is the head still on the engine? and engine still in the car?

[votivequagmire]

Yes and yes to the previous question.

I've purchased a right angle drill attachment now and am planning to drill it out as advised above.

I've also picked up a reverse thread drill bit in the hope of turning the stud also whilst drilling.
And just in case, I've picked up a stud extractor set although I'm told for such a small stud they are rarely very effective.

I'm hopeful that I now have the necessary equipment to extract the two studs which just happen to be the last two on the bottom of the head next to the bulk head

Now all I need is for it to STOP F***ING RAINING FOR JUST ONE DAY !!!!

[bdx]

Use a small pilot first 2-3mm ~

watch the depth

[maxfield]

Try and centre punch it first.

[votivequagmire]

Centre punch and pilot hole ... got it.
Was thinking of using tipp ex on the drill bit to give me a visual means of determining how deep I should be going.

Thanks all for your advice.

[e30maddog]

hope it works out for you although as i said above, ive never had any luck with those reverse thread jobbies but let us know if it works out, you might give a bit of hope for the reverse thread stud removers

[tim_s]

I'm in the midst of a similar job on the coxster. Not sure if you'll find the same with the bm, but on the coxster where the bolts (bolts not studs on the porsche) have snapped it was due to the studs being completely rusted into the head, so despite loads of heat which should theoretically have expanded the alloy head way more than the steel bolt, and thus allowed my grippy stud extractor thingy to grab the remaining stud (they've not snapped flush) the stud's rusted in too badly to remove. This imo is an important point - if the studs snapped due to misfortune or whatever, fair enough try extracting, but if they snapped due to excessive torque even when heated up and still won't come out, it's unlikely you'll remove them with stud extractors which ultimately rely on the bolt being able to be undone. I'd stray from using the reverse tap style things as they're so hard that if you snap one in, drilling it out would be a nightmare.

So on the porsche I've taken to drilling out. It's a pain but is not impossible. On an e30 you'd need good clearance, you'd at minimum need to undo engine mounts and jack the engine as much as poss... have had to use solid carbide bits, nothing else will get through the bolts well, and had to be v careful on keeping it drilled central, on bolts with access issues this is particularly difficult. I've found drilling out then retapping has given a good strong thread without helicoil inserts.

Hth
Tim

[aeberbach]

What an utter bastard of a job. I had the M6 bolt that attaches the front cam pulley shroud break off recently and it's staying there.

Here's a page that may help:
http://www.asashop.org/autoinc/may2003/techtotech.htm

[votivequagmire]

What an utter bastard of a job. I had the M6 bolt that attaches the front cam pulley shroud break off recently and it's staying there.

Here's a page that may help:
http://www.asashop.org/autoinc/may2003/techtotech.htm

Cheers for that, it was helpful

[sanitroc1]

I don't know if this will help you but I had six broken studs on my 325 when I bought it . Someone said to refit the manifold and use a drill bit the same size as the holes in the manifold to put a small countersink in the top of the stud . This gives you a center point and stops the drill wandering when you the drill the stud . I got five of mine out using this method before the extractor snapped which was a snap on one .