Stud removal

[Deptford Draylons]

i have a cylinder head I'd like to strip down. Each intake and exhaust port has 4 studs and 8 studs for the cam tray above it and a few others for ancillaries. A few of the smaller ones came out using two nuts, but that was it.
Can any recommend a good stud removal tool and are there any that will leave them usable, or will it chew the threads and render them useless ?
M6 to M10 studs.
Thanks

[GreenV8S]

You could use a stud remover - essentially a split collect with an internal thread which grips the whole outside the the thread. But they're a bit spendy, and if you need that much torque you have to wonder whether you're going to break the studs.

[tapkaJohnD]

You don't want one of these -gauranteed top chew the thread.


You might use one of these:

as described above.


But one of these:

will be easier to use. They contain a set of cams inside that grip the stud evenly along its length and cause no damage. You just put them over the stud and turn, either way.

John

[Mignon]

There are no types of stud removal tool that will remove threaded studs without destroying them. Only if the stud has a long enough plain section of shank below the thread that you can get the entire length of the cams in the stud remover onto it can such devices be used safely and that doesn't generally apply to most cylinder head manifold studs.

Wind two nuts on, lock them together leaving the top edge of the top nut just proud of the top of the stud and then whack seven types of merry hell out of it with a small hammer to shock the stud threads loose. Then try unwinding the stud again.

[tapkaJohnD]

If you don't mind destroying the stud!

WELD a nut to the top, let it cool and then take the 'bolt' out with a spanner/socket.
Always tighten the stuck bolt/stud first, then 'ease' it out, to and fro, like cutting a thread with a tap.
If the stud/bolt starts to 'squeal', STOP! It may be about to break.
More heat, penetrating oil, more easing, until it comes out.

John

[M32Guy]

I use those cam type stud removal tools on the 1.8 Vauxhall engines all the time. Oil coolers are quite common for leaking and require removal of the exhaust manifold and it's studs to gain access. Haven't had a problem reusing the studs and nuts yet

[Deptford Draylons]

Thanks all, I think I'll try the cam type tool and see how it goes.
On a related question, would the studs holding the exhaust and inlet manifolds just be 8.8 grade material ? BMW prices for each stud seem a tad expensive at at around £5 each for something like M6 stud of about 35mm up to £8 each for similar M8 studs. Oddly, the M8x90 studs are a more reasonable £1-2 each that hold the cam tray down. Would the exhaust studs be different grade for the heat ?
Thanks