59AB Stubborn Studs

[Smitty]

I have a flathead V8 with about the most stubborn head studs I have ever seen. Nothing seems to be able to loosen them: penetrating oil, oxy-acetylene heat, stud remover. I have managed a few and broken a few.
Thoughts?

Thanks, Steve

[rotorwrench]

The studs that go into the coolant passages can sometimes get corrosion so bad that they literally weld themselves in place. If you tried heating them red hot and they still won't loosen, they may have to be removed with special equipment like the MDM set up (metal disintegrator). Some machine shops have them.

[Andy]

Candle wax!!! Don't laugh. Heat the stud up some and melt candle wax around the threads. It is majic.

[JSeery]

Most people swear by the weld a nut on the broken stud method. You can also blow the studs out with a cutting tourch.

[papanomad]

either candle or bees wax and heat. may take 2 or 3 times and stubborn studs may take more, but will work.

[drolston]

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Using a long bar, I broke off 5 head bolts on the left bank; broke two more using an impact wrench at full power. On the right bank, all came out cleanly using the impact wrench, but with a gradual approach I learned about on this forum. I have a battery powered impact wrench with three power settings. I started at the lowest power setting and tightened for a second or two, followed by no more than two or three seconds loosening. Repeated that cycle several times, and a few came out on the low setting. Then I raised the power to the middle setting and repeated the back and forth hammering. It took up to 5 cycles, but all came out unbroken. If you have to go to full torque, you are probably going to wring them off. Then it is a job for the machine shop.

That was bolts and you are working with studs, which makes this technique tricky. If you can find two different size nuts that fit the stud threads (maybe 5/8 and 11/16), jam them together on the threads with the smaller on top. Use the smaller socket to attempt to tighten, and the larger socket to loosen.

How you get the nuts off of the stud after it comes out will be an interesting challenge after having the impact wrench jam them together! My suggestion: never reuse studs and nuts are cheap compared to machine shop work, so pitch them.

All of this was after several days of repeatedly dripping Liquid Wrench on the threads.

[40 Deluxe]

Originally Posted by JSeery

Most people swear by the weld a nut on the broken stud method. You can also blow the studs out with a cutting tourch.

Suggestions when using the blue wrench: First drill a hole through the center of the broken stud/bolt completely through into the water jacket. Use about a 3/16" or 1/4". Be sure to drill straight so you don't drill into the block threads. This gives an escape route for the slag so it doesn't blow back and make a mess.
Make sure the torch cutting tip is clean so you get a precise flame. Concentrate the flame on the stud, through the hole you drilled. When the broken piece is red hot (not before) hit the oxygen lever, and stay on it until all the stud metal is burned up and blown down through the hole. Aim for the red hot pieces clinging to the block threads. You won't hurt the threads because they are not red hot so won't burn. With a little practice you will end up with just a few crumbs left in the block threads. Blow them out with compressed air then run in a thread chaser. You will end up with original undamaged threads!

[Yoyodyne]

Originally Posted by JSeery

Most people swear by the weld a nut on the broken stud method. You can also blow the studs out with a cutting tourch.

^^^^This. I broke 30 studs on one 21 stud block. If Kroil doesn't work, I just go ahead and twist them off, then TIG weld a nut (and/or washer) to the broken piece. Heating the stud to welding temp and letting it cool breaks the rust bond, and they come right out afterward. I prefer TIG to MIG because it's slower and heats the stud more and allows more control of the process, causes more shrinkage of the stud too.