Stud removal

ie "Electrical Discharge Machining" An electrode contacts the stud in a coolant bath, creating a continuous spark which erodes the stud away. It's slow, but it works.



They can be drilled and tapped out, but it has to be center punched and drilled dead center with progressively larger drills until you get to the root diameter of the thread, and tapped v e r r y carefully. If you break the tap in there, you most likely WILL have to go to the EDM machine, because the taps are so hard there's no drilling them.



I do it with mine, but I'm a graduate toolmaker with training and experience, and it's still nervewracking hairy work. Find a mechanic with experience and guts.



If they're fused (rusted fast) to the block, manifold etc., then penetrating oils don't, and neither do easy-outs.



Sometimes passing a current from the stud to the base metal with a welder will heat the interface enough to loosen them.



An interesting method in 'Vintage Truck' magazine last year, advocates using plain water as a penetrant. Keep it wet and tap it with a small hammer several times a day. I used this method on a half-dozen manifold studs on a 254 and 3 or 4 of them turned right out. BUT another two didn't either.



Good Luck and some expertise

Larry

Sometimes this method has worked for me: with a small pick and wire brush, completely clean the crud from the base of the stud. Sometime heating with a small torch will help burn away the stuff. Then after soaking it with a good penetrating oil, wrap a rag around the stud to make a 'seal' of sorts, and with an air chuck with a rubber tip, 'force' the oil down into the threads.

Put the block in a engine stand , turn it over and try filling the water jacket with muratic acid and let it work for about an hour. Use heavy duty latex gloves and respirator. Can burn your hands and lungs, but effective in removing corrosion

You should have a mobile stud removal service in your area.



3 or 4 years ago I needed the exhaust manifold replaced on my Rodeo. I was at the mechanics during the removal process and freaked out when one of the manifold studs broke off flush with the block. Common problem with Rodeos I'm told.



Not to worry they said, we'll get the stud guy in.



Stud guy says I?.



Apparently there is a specialist guy set up in a van who has seen it all studwise, has all the equipment and makes a living from removing broken and/or stuck studs.



Failing that, I would suggest liberating the block temporarily from its present location and taking it to an engineering workshop with a decent size milling machine. They will be able to set up the block and accurately machine out the broken studs without damaging the threads.