Seized exhaust manifold studs

[overrun]

Any tips for removing these from an alloy head?

 

 

Double nutting them only results in the studs feeling as though they will snap, rather than turn, or both of the nuts undoing on the threads.

 

I have tried soaking in WD40 and heating the stud with a blow lamp - something I am.not too keen on doing.

 

Still to try is a soaking in Plus Gas (will get some tomorrow) and lightly tapping the studs.

 

Is it worth using stilsons directly on the stud, as they will get the best grip?

At present, I can still thread nuts on, no problem.

 

I only decided to replace the studs incase they gave future issues. :L

 

Any suggestions are welcome. I don't want to remove the head, unless I end up snapping tthem, though!

[twosmoke300]

Weld a nut on the stud. Then wait til it cools

[Station]

Two have snapped on Saab engine. Going to take head to engine place to get ported etc and have studs helicoiled.

[gordonbennet]

If Plus Gas doesn't do the job, think i'd leave them be until they really need to come out for some rweason, wire brush the threads well apply some coppaslip and put some good old brass nuts on or if impossible to find some stainless ones instead, maybe put an extra nut on each to protect the exposed thread.

[overrun]

Weld a nut on the stud. Then wait til it cools

I wasn't sure if that was the way to go, when the head is aluminium?

 

If the soak and tap method gets me nowhere, that will be the thing to try, though.

An ie cube on the stud is also recommended, after welding, iirc.

[spike60]

If you're only replacing the studs in case they cause future issues why not let sleeping dogs lie and leave alone if they don't want to play? If they snap or pull the head threads it's a load of grief perhaps avoided.

[explosive-cabbage]

Google 'Footprint Grips'

Most highly-valued price of workshop equipment we have.

[plasticvandan]

Heat the flick out of it,friend and I used his oxy acetelene torch on a very stubborn reliant cylinder head to free it,no probs.heat is your friend.

[Bren]

If the have to come out ,as posted earlier weld a nut on the end.

 

To stop weld spilling over put a washer on first.

[overrun]

Google 'Footprint Grips'

Most highly-valued price of workshop equipment we have.

I am aware of these, my plumber mate uses them, or did.

Will see if I can borrow them.

 

I would rather replace all of the studs for the new stainless ones I have, but I hear what people are saying.

Hopefully the threads aren't too fucked, now.

 

Cheers all.

[Stixy]

Gently heat the head arounf the stud with a blow lamp  but gently !

 

The alluminium head will expand quicker than the steel stud , so a bit of heat and wd or plus gas then try and undo it 

 

When you build it back up use stainless steel M8 Grub screws 

 

http://www.ebay.co.uk/itm/M8-SOCKET-SET-GRUB-SCREWS-PLAIN-CUP-POINT-PCP-A2-STAINLESS-STEEL-ABOLT-FTB-/121258450517?pt=UK_DIY_Material_Nails_Fixing_MJ&var=420226393458&hash=item1c3b911e55

[TRW]

As Stixy has said, heat the Alloy head (slightly) to expand the area around the stud loosening it's grip. A gentle 'blow over' the area with a butane torch would be ideal.

 

Welding nuts onto the manifold studs beforehand will be beneficial to the undoing method. A good grip is what's needed in the undoing.

 

P.S - If it creaks on undoing, time to stop. More Plusgas, time to soak in, then heat and finally more undoing.

[twosmoke300]

Give each stud a good hard crack on the end with a hammer . This will shock any rust loose. Then weld the nut on the end . Won't harm the alloy head but the heat generated will break the rust bond or dissolve any studlock .