Manifold stud removal

[Ritchie Wilson]

I have had success with 3 rusted head studs on my Ruby using heat combined with plumbers freeze spray, penetrating oil & a cup of tea.

I warmed up the stud and area of the block around the stud. Not too much just enough so fingers cant touch it.

Then a cloth placed around the stud base and a liberal dose of freeze spray. The cloth stops the block from being cooled. The stud is cooled quickly and contracts then remove cloth and spray it with penetrating oil.

Boil the kettle, make a cup of tea.
Drink tea.

I then used the type of stud extractor as described by Hugh Barnes.

Heating, cooling, cycling and tapping all have in common that they subject the rust between the threads to forces which would disrupt the structure of the rust crystals jammed between the block and the stud. Only after the rust has been disturbed could lubricant be expected to be able to penetrate between the threads.
Very strong heating might change the chemical structure of the rust so that it doesn't lock the threads together, but the temper of the stud may also suffer - making it easier to break.

The very well thought of (in New Zealand) Japanese tool brand Koken makes stud removers in imperial sizes, but the devices illustrated have metric markings suggesting that metric removers are serviceable for imperial sized studs.

The hardened steel, left hand thread "stud extractors" are only suitable for removing well lubricated fasteners which have broken for some reason. The two occasions I used one on rusted bolt fragments they broke. On the first occasion, an aluminium motorcycle engine, spark erosion saved the day at considerable expense. The second experience was with a broken fastener in a Record rebate plane which I never did extract. I bought another one. There won't be a third occasion.