+- Austinsevenfriends (https://www.austinsevenfriends.co.uk/forum)
+-- Forum: Austin Seven Friends Forum (https://www.austinsevenfriends.co.uk/forum/forumdisplay.php?fid=1)
+--- Forum: Forum chat... (https://www.austinsevenfriends.co.uk/forum/forumdisplay.php?fid=14)
+--- Thread: Head stud removal (/showthread.php?tid=9509)
RE: Head stud removal - John Mason - 04-08-2024
I am with Chris KC and Robert Leigh on this one for removing broken studs. Use the head as a guide to drilling. I have made two inserts to put down the head stud hole to guide the drill bit. A small holed one for pilot hole and larger hole for drilling out the stud. All as copied from the big red book. It all means you can safely drill with a hand held drill.
John Mason.
RE: Head stud removal - Denis Sweeney - 05-08-2024
Thanks for the comments and advice, a Blue Spot impact stud extractor tool duly arrived today but the plus gas will be a couple of days to arrive, none of the local stores had any.
Chris, do you use an impact tool that imparts torque on the extractor or a hammer setting on an electric drill?
Bit concerned about hitting a cast iron block with too much wellie….
Guess no one has tried the welding to the stud method, would be interesting to see how it works in reality rather than in a video, I guess if there was a knackered old head it could be worth a try but not sure I want to risk it on this head.
Cheers
RE: Head stud removal - Chris Garner - 05-08-2024
Denis. I just use manual" force " . To my mind it's more controllable. Make sure the jaws are as far down the stud as possible.
Just one caveat which I know Ruairidh will concur with. If the studs are original and have never been removed, on several blocks I've found them almost impossible to remove without going to extreme measures such as induction heating.
RE: Head stud removal - Denis Sweeney - 05-08-2024
Chris, I have four blocks, all of which have been in my possession since 1984 and have sat in my garden shed wrapped and coated in oil. So I think it is a pretty fair bet that the studs would be original.
The one I am working on is the only one that is around the same engine number as my Ruby, just slightly later. All the rest are, I believe earlier, as I cannot readily see engine numbers on them.
I cannot at present detect any cracks on the top face but will check that and the first cylinder has quite a score down the bore and may need to be re-sleeved, but we shall see.
Will let you know how we get on.
Cheers
RE: Head stud removal - Denis Sweeney - 14-08-2024
Thanks to both Chris KC and to Chris Garner for their advice re Blue Dot stud remover and the use of Plus gas.
Having soaked the studs with PG for several days I successfully removed the first 7 studs, 4 on the left and bottom 3 up the middle, these came away surprisingly easy............. at which point my not so "youthful" exuberance took over and the 8th promptly broke, again as correctly predicted by Chris KC .
Stud 9 at the centre top then came away pretty easily but 10 bottom right was not wanting to budge and having broken the 7th I left that till later. 11 came away without too much effort but 12 again was being difficult. Unlucky 13 also broke a little too easily for my liking without much effort being applied and 14 would also not budge.
I have now heated the three remaining studs, only with a blow torch, no Oxy available to me and continued to soak with PG for a couple of days now.
I do have a pillar drill but do not have access to any other machine tools to make these myself and other enthusiasts locally are not able to assist. I now need to drill out at least two broken studs and referring to the details of the drill guides in Woodrow, does anyone know of a source for these drill guides or know of a machine shop who would be able to turn these up??
Thanks again for the advice folks
cheer Denis S
RE: Head stud removal - Reckless Rat - 14-08-2024
Bugger!
RE: Head stud removal - Charles P - 14-08-2024
With a sharp centre punch and a pillar drill you can sort them out.
The drilling guide, as illustrated in Woodrow, isn't your saviour. In my experience it is less accurate than the centre punch/pillar drill. At least with a pillar drill you're not working blind and just trusting that any accumulated movement on the studs isn't significant.
RE: Head stud removal - Alan - 14-08-2024
I use a lathe centre drill to drill a pilot hole first. They tend not to wander like normal small drills.
RE: Head stud removal - Chris KC - 14-08-2024
I think you did well Denis!
Just keep in mind that you will forever curse yourself if you don't drill them out true.
One thing you can do is replace a few studs temporarily and use the head itself as a guide.
Any fairly snug-fitting drill bit will be guided by the head, and will mark a centre on the top of the offending stud, to guide your punch &/ or drill (I think Robert Leigh suggested this above).
The Woodrow tools are great in principle, but in practice the hole sizes in the head are distinctly variable. If you can find any bolt or scrap of tube which fits snugly and drill it down the centre, it will have the same effect.
Drilling down the middle of bolts is a challenge but can be done:
(1) drill a hole in your machine vice using the tapping drill size for the bolt you want to drill (OK, I have an old machine vice - but the point is it will sit dead flat and can be bolted to the bed of the drill).
(2) start the tap in the drill chuck (turning it by hand), until it gets too tight to turn, then finish by hand (this gets you a nice vertical start)
(3) put the tapping drill back in the chuck, and lower so the bit is located in the threaded hole; in this state bolt the vice to the drill bed.
(4) raise the chuck, remove drill bit, replace with a pilot drill say 3mm dia - not too small; screw your bolt down into the vice.
(5) now you can drill down the centre of the bolt in perfect alignment - well, you stand a good chance...
Of course you could do the same trick with any bit of tube etc that will fit, as long as you can stop it spinning while you drill it.
RE: Head stud removal - Ruairidh Dunford - 14-08-2024
I use a cylinder head with a drilled top hat bush to get the pilot central.
You will need to put some of the studs back in, clamp it down with some nuts, then put the top hat bush inside the stud hole and drill the pilot.