Studs grown to the alloy?, if so you might have to soak them with a bit of WD or similar,
Penetrine maybe, other than that get a small flat bladed screwdriver and gently tap it in around where the housing meets the head and then give it a few taps with the handle of a hammer.

sounds like! yep I soaked it in WD too

tried many taps with a rubber mallet to no avail - didn't want to chip in too hard with a screwdriver between the head and the housing in case I caused some damage

If you use a screwdriver or something similar, your more likely to damage the housing
but still be gentle with it , you will get it apart. Work around it bit by bit .

I have had some that needed smashing off.
Try Penetrene or another good penetrating oil if you can find one. WD-40 is not penetrating oil.

again, thanks for the advice

will grab some penetrene tomorrow and let it soak all arvo before having another go tomorrow evening

would it be easier if it was warmed up up cold?

just thinking about expansion v shrinking??

You could try a hot air gun on it , see how you go .

I like to give things a blast with a heat gun and then another squirt with the penetrating oil. It seems to draw it in better.

The problem is corrosion from the steel studs and the aluminium casting. (reaction from dissimilar metals) It helps in future if you coat the studs with something to prevent the corrosion from happening again. I use Permatex (Loctite) No3 non hardening gasket cement. It stops the corrosion, seals the gasket and because it is non hardening you can always get it apart later on.

I tried an ink knife (paint scraper) which is softer and broader than a screwdiver by far to no avail too

I don't have a heat gun tho so was wondering if engine heat would make a difference?

am prepared to buy a new thermo housing if I have to get the bugger off, just don't wanna damage the head :/

I did a thermo housing 2 days ago for 1970minik, all 3 studs were corroded in real good.
I sprayed them with RP7, locked 2 nuts together on top of 1, heated the alloy around the stud with my Makita hot air gun (550C) and when nice and hot (and expanded) it unscrewed fine. Repeated for the other 2 studs, all good.

Wire brushed the studs clean, stuck an 8.5mm drill through the thermo housing holes, all good to go again.

Personally I prefer to use Unbrako socket head capscrews here instead of studs on my motors. When you unscrew them it cracks the corrosion off. I smear em with Permatex #3 gasket cement on assembly, this helps too.

BTW I luv my hot air gun...

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Had a play with Minimaxxs old clubman. Pulled some panels off and striped most good bits off it. Poor thing

I need a top dash pad, with 2 warning lights

Got a spare buddy?

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You're so square
Baby I don't care

Yesterday I continued pulling my engine down for it's freshen up. Flywheel off, clutch housing removed & valves out of the head. Don't know who built this engine but the amount of clear silicone they used is beyond a joke!

Discovered that three manifold studs are siezed in the head, not even big vise grips will budge them, & the heads "unleaded conversion" hasn't been done, so need to find someone in Brissy who knows what they are doing with inserts as it's a pretty rare head, 12G938! The 35.5 inlets & 29.2 exh valves look good in it though!

Shane

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If it's not a Cooper S, the mini was designed to be modified!

Sorry adam, i need the top crash pad for my clubby nad it doesnt have the 2 warning lights in it. Its a real early 71 one of the first 400 cluubys.

Got the horn working, turns out it was a dodgy earth.

Replaced the indicator stalk assembly.

Tried getting the wipers working......until I opened up the wiper motor and discovered it was just a casing full of rust and corrosion.

Now trying to determine why I have no high beams.

replaced the gasket on side plate massive oil leak now fixed

rear pockets lined with carpet

replaced front left parking light bulb

next thing is getting it registered

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71 Clubman 1100