Seized AG dyno unit, any tips

Quoted message said:

I thought this morning that i'd service the Sturmey AG Dynohub on my
78 Superbe, but 5 minutes into the usual dismantling, it became clear
that the chrome plate and magnet unit was rusted in and wouldn't just
drop out as it has always done with the others that i've serviced in
the past. I've soaked the area in WD40 and bike oil for 10 hours, then
tried inserting a broken spoke to knock it out from the righthand
side. This just result in bending out the chrome cover around the
holes. I've hit it inwards to try to break the rust hold and i've
tried to insert a screweye in each of the four holes, with wire and
hammer as a puller, but to no avail. Anyone have an idea how i could
get this out. I've managed to have a tinker with it and got the
internals out by simultaneously unscrewing the axle and ballring, but
still can't get to the left hand cup which as luck would have it is
grindy and probably shot. Any suggestions would be greatfully
received,

Is there a compelling reason to open it _right now_?

Some tincture of time and some penetrant might make this a project for a
later day. Before you do more damage. Riding a 'stuck' piece with
regular application of lubricant can do wonders.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

Cheers for the reply, i was planning on selling the Superbe this week
and thought i'd do the next owner a favour and overhaul all the major
parts. I think you're right, looks like a soak and wait situation.
cheers, Nick

Following my question just in case anyone has a similar problem with
badly seized components, i managed to shift the magnet and its cover
plate after 14 days of soaking, and each day spending about 30 minutes
banging and tapping it in various places. I almost gave up on it, but
just as i was going to reassemble, it mysteriously shifted a fraction,
so i continued.

I used the short end of a 3mm allenkey inserted in the
coverplate hole and tried to get circular movement. It didn't move
until the magnet shift by a few mm on the 12th day. Also i removed the
internals and inserted a 4" socket bit throught the back of the left
cone and hammered like a monkey, which pushed out the coverplate, a
few mm at a time, banging it in and out repeatedly for the entire two
weeks. The magnet and plate finally gave up the ghost when i inserted
a flat end punch in through the rear magnet holes and tapped the whole
lot out. I've sadly killed the cover plate, looks like it's spent a
weekend in Baghdad, but hopefully i'll be able to buy another one, it
looks like the GH6 coverplate is identical. The magnet had rusted and
bonded to the interior of the hubshell, which needed some cleaning,
but is still pretty good. I'd love to see a modern hub go through the
stuff a Sturmey can take and still work afterwards. Hopefully it'll go
back on the Raleigh Superbe OK and i'll be able to pass it on to the
next sentimentalist as fully serviced and ready to do another 20 years
service.
cheers, Nick.