:icon_mad: so i'm gearing up to rebuild the 7m which had hydrolocked. lo and behold bolt #6 started to round up :cry: i might be able to force an 11mm in there and hope it 'fits' to get it out if not,how do i get it out? much thanks in advance
ever had an head bolt round up on you?
- Thread starter pelper87t
- Start date
I had that happen once. I ended up have to drill the head of the bolt off. Once the head was drilled off, I was able to pull the cylinder head off and the rest of the bolt then backed out easily, should be easy to clean up at the machine shop (as far as the bolt shavings)
If this is for a stock head bolts go get a (iirc) 12mm 12pt and hammer it in the bolt and break it with a long breaker bar.
i used a slightly larger torx bit and a large breaker bar and a hammer and a friend to crack it off when i stripped mine.
I'm gonna come off sounding like a dick here, but I learned my lesson the hard way by almost rounding off the diff drain bolt on a Miata once. Use the right tool. 
Seriously if it's a 12 point bolt, use a 12 point socket. If it's a 6 point bolt, use a 6 point socket. This will prevent a LOT of headaches man. Oh, and if you can manage to get it in there, PB Blaster is your very best friend the night before you disassemble.
Seriously if it's a 12 point bolt, use a 12 point socket. If it's a 6 point bolt, use a 6 point socket. This will prevent a LOT of headaches man. Oh, and if you can manage to get it in there, PB Blaster is your very best friend the night before you disassemble.
Err... the stock head bolts are 6 point allen heads... unless he's using the wrong size, it's near impossible to have the wrong tool.
:3d_frown:I know the bolts are 10mm hex pattern, all the other bolts are out just this one left how it got rounded in the first place i have no idea
most likely not inserted all the way into the hex fitting before someone started putting it on/ taking it off.
just had this happen to me, on arp headbolts. lots of blood sweat and tears over one headbolt. right socket didnt work, tried shocking the bolt, hammering on a smaller size, using those spiral sockets, hammering on smaller spiral socket, torching the block while applying pressure with spiral socket. last thing i tried was an air hammer with a chisel tip to try to get it to turn a little bit, nope. so i drilled it out with a 31/64 bit. then i thought thank god ill just unclip the injectors and feul rail ect. and pull it off with the intake manifold on... nope. the wiring harness goes through it and the bolts are stripped on the upper half of the manifold. i hate my car.
A lot of the time I have seen this is because of the oil in the head when taking it off. When you stick the bit down into the hole it feels like it goes all the way down but the oil can hold it up, either tap it with a hammer lightly till the oil comes out or just take compressed air and blow the oil out before starting. As for getting it off, you can either try the oversize which usually doesn't work because the head of the bolt will break first or drill the top off. With enough cutting oil and slow speed you will not send chips flying around. Btw once you get the head of the bolt off you will want to drill a smaller hole into the bolt then use an easy out as pictured above to remove the bolt before taking off head.
On the drills bit front. Do not cheap out. I used a Cobalt drill bit. Made short work of the head bolt. The HSS drill bit will fail.
Just for clarification, not the brand Cobalt, but a drill bit made out of cobalt. Purchased at Fastenal.
Just for clarification, not the brand Cobalt, but a drill bit made out of cobalt. Purchased at Fastenal.
i used these to remove the stocks head bolts on my 89 and my moms.I wondered why they had that skinny section at the bottom and metaphysico mentioned oil in the dead of the bolt,i figured that's why it was.Am i right? it also made a really good section on the bolts that made removing them a breeze.
they are Kobalts i got at lowes.
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they are Kobalts i got at lowes.
I rounded out one of my stock headbolts and didn't have any luck getting it out with a larger hex socket. I ended up using a Sock-It-Out bolt extractor to remove it. It worked perfectly. I still have it laying around, if you're interested in it let me know.
7EMPIRE;1599716 said:i used these to remove the stocks head bolts on my 89 and my moms.I wondered why they had that skinny section at the bottom and metaphysico mentioned oil in the dead of the bolt,i figured that's why it was.Am i right? it also made a really good section on the bolts that made removing them a breeze.
they are Kobalts i got at lowes.
.
No... the ball end allen keys are designed so that they do not need to be straight in - they work at an angle as well. Unfortunately, they sacrifice a fair bit of strength for this feature, so it's not uncommon to see these with the ball end snapped off. There's no way I'd use a ball end on the head bolts...
use a dremal and a cutting wheel to cut off the bolts head. once its off the head you cand make two flat sides on the remaining stud to use a small wrench to back it out.