Stripped Head Stud Hex Socket

[mattis96]

hey guys i was pulling down a spare engine and got to the last head stud and i kinda made it worse and stripped it, so its now rounded where the hex socket go's (i had no problem getting the others out at all).

So i need help on what to do to get the still torqued head stud stud out, i have stud extractors but dont think they will work, and i only have the basic tools in the garage you could say to use. i tried googling and no real help there with it, only saying to drill it and it should make a 'pop' sound and you can get it out then?

Thanks

[GTRNUR]

You need a metrinch socket set, or at least a loan of a socket that will fit the head bolt. They grip the flat of the bolt. There is a chance that will get you out of trouble.

If you've managed to stuff the head bolt too, I dare say that most thing mechanical are best not done by you. Ive seen whole cars destroyed by people that have their ambitions mixed up with their capabilities, the result of which was a good 1/2 of everthing removed from their skyline was rooted. Some people shouldnt have tools, and especially hammers.

[mattis96]

It's an Allen key socket that the head studs use which I rounded. I understand what your saying about some people shouldn't do engine work, but I'm fine doing it mate.

Is there anyone else who's had this problem and fixed it at home?

[ARTZ]

You need a metrinch socket set, or at least a loan of a socket that will fit the head bolt. They grip the flat of the bolt. There is a chance that will get you out of trouble.

If you've managed to stuff the head bolt too, I dare say that most thing mechanical are best not done by you. Ive seen whole cars destroyed by people that have their ambitions mixed up with their capabilities, the result of which was a good 1/2 of everthing removed from their skyline was rooted. Some people shouldnt have tools, and especially hammers.

Thats a bit of a rough call mate, here is a guy thats willing to get in and give it a go and your bascially calling him a numpty for stripping a bolt..

I have stripped and broken plenty of nuts, bolts, screws in my days , its part n parcel of playing with old cars, especially with limited tools at your disposal, and i bet if you ask any mechanic or engineer they will have stripped a bolt or two in their days..

I sent my car to the dealership to get serviced and they stripped the radiator drain plug causing it to leak and overheat my car, do you think i should give these knobs my hard-earned?..

To OP, i dont know how to help you sorry i usually call a guy to come fix me messed up bolts...I just dont have the tools to do it and he makes it look so easy cause he has cool tools that can only be bought on the black market..

[mattis96]

It's all good mate, I wasn't offended... But yeah like I said I got them all off with no problems at all except the last one as it was already a little stripped from a previous owner, I just made it worse. I'd use an easy out but it's still torqued to the block.

[t_revz]

i deal with torx hex screws etc day in day out and when they strip i usually put the next size bit in and smash it home then they crack.maybe .5-1mm will go in.or get a drift and hammer and give the head of the bolt a good tap and try again. might help tightening a few of the other bolts back up first if you havent already.

[ARTZ]

i deal with torx hex screws etc day in day out and when they strip i usually put the next size bit in and smash it home then they crack.maybe .5-1mm will go in.or get a drift and hammer and give the head of the bolt a good tap and try again. might help tightening a few of the other bolts back up first if you havent already.

this is exactly what i was thinking I would do in this situation.but didnt want to give advice cause i hadnt done it before...

[mattis96]

yeah i did think the same thing to but that means i'd have to go buy a 11mm allen key socket and i havent seen them sold seperately anywhere really, and i wouldnt want to try smash it in there and make it worse. but i will try it, thanks.

[doo doo]

Have you tried two nuts? Screw them tightly them together on the stud and unscrew using the bottom nut. You shouldn't be torquing the studs in by the way, just nippng them down slightly with the allen key is sufficient. Make sure you have clean clean threads (use a cleaning tap and make sure there's absolutely no crap in the hole, an air gun with a tube reaching down to the bottom of the hole will do this) before reinstalling studs. If you're not already doing this of course.

[Duncan]

good call on studs....but I think from the description he means head bolts. They use an internal hex head.

[mattis96]

yeah i did mean the internal hex head on the head studs, what do other people do when they encounter this problem?

[mad082]

if the stud is a 10mm allen key then you'd really want a size between 10 and 11mm, unfortunately though, i don't think there is one.

if you end up not being able to find an 11mm allen key sold seperately let me know as i can get them through one of my suppliers at work. they aren't that cheap though. even doing it at cost price you'd be looking at about $30 by the time i sent it to you, so it would be cheaper to go to your local bike shop and see if they could get you one as they retail at about $25. if i dealt with the company more often i could just get one added in with an order and that would drop the price, but since i rarely get stuff off them, i'd be paying about $8 freight just to get it to me, then postage to send it to you. if you go to your local bike shop, ask them if they deal with pacific brands. if they say yes, then they could get it for you. the brand is Park Tools, and the part number is RHR11.

[doo doo]

good call on studs....but I think from the description he means head bolts. They use an internal hex head.

Yeah i wasn't sure but studs do have an internal hex drive too, but it's 5 or 6mm. If they're head bolts (then the head is still on) then I might also add that you shouldn't remove each one one at a time, but back them off half a turn each in the reverse order of the tightening sequence. This way you won't potentially warp the alloy head (likewise with studs anyway). In the case of them being bolts you could try a rattle gun. If you need oversize you could also try imperial for a small increment of size increase (eg 7/16ths is about 11.1mm) and smack in in with a hammer as suggested, you won't be using the bolt again so don't worry too much. If you drill the top off the bolt off this will also work. If it is a bolt and not a stud. Maybe post a pic so it's clear.

[mad082]

Yeah i wasn't sure but studs do have an internal hex drive too, but it's 5 or 6mm. If they're head bolts (then the head is still on) then I might also add that you shouldn't remove each one one at a time, but back them off half a turn each in the reverse order of the tightening sequence. This way you won't potentially warp the alloy head (likewise with studs anyway). In the case of them being bolts you could try a rattle gun. If you need oversize you could also try imperial for a small increment of size increase (eg 7/16ths is about 11.1mm) and smack in in with a hammer as suggested, you won't be using the bolt again so don't worry too much. If you drill the top off the bolt off this will also work. If it is a bolt and not a stud. Maybe post a pic so it's clear.

before i posted up before i went looking at the imperial sizes that they do and it seems to jump from 3/8" to 7/16" (so just under 10mm to 11.1), so he'd be best of keeping it metric and going an 11mm as it will be easier to get in, hwever i think that even 11mm may be too big. really want a 10.5mm

another tip i've found to be useful is if the allen key is a little bit rounded, cut a bit off the end so you are using a section with nice sharp edges. you can also get a paste that has some grit in it to help it grab. there's one product called screw grab, and another called regrip (the brand of that is recoil, the same company that makes helicoils, etc). i don't know if any automotive shops will sell them, but i would assuming engineering/specialist tools and fasteners shops would.

[zebra]

If all the above fails and you cant get an 11mm bit to fit, heat the bastard up and then whack the 11mm bit in, might not come out ever again, but should soften and expand the head bolt head enough to get by.

Also try looking at some whitworth sizes, but I'm not confident of any one in Aus carrying whitworth size allen head sockets.

[FineLine]

As a last resort you may have to drill the head off the bolt. Bitch of a job as they are hardened but i believe it could be done with a bit of care.

[GTRNUR]

Sorry wasnt tryting to have a go at anyone... Sometimes I come off a little blunt. I guess the point I was making is you have to do well to round out the end of a grade 12.7 high tensile bolt.

Your only option is you cant get anything to grab it will be to get yourself a 12mm cobolt drill bit, and slowly drill the head of the bolt off. Use PLENTY of drill/cutting lube and drill it slowly. If you go fast you'll burn the cobalt bit and it will not cut anymore.

Done properly a cobalt drill bit will drill high tensile steel like its butter.

[doo doo]

Hey Mattis you're in caboolture- I've got cobalt drill set so if you're stuck let me know and I'll pop up and help you out.

[ARTZ]

Try this guy maybe..

http://www.mobilethreadfix.com/

I had a guy come to drill out 5 broken exhaust studs, he did all 12 and replaced them all with newies for about 100$ so shouldnt cost you much and saves alot of headache

Edited December 8, 2010 by Arthur T3