4AGE cylinder head plug removal

[Ivan141]

Has anyone ever removed the oil gallery plugs off a 16v 4AGE head?
My early bigport head is currently off for vapour blasting so I am expecting to get it back with blasting media contamination that could potentially ruin an engine really quickly if it's left in there.

There are 2 small hex grub screws that allow access to some oil channels but they seem to be rounding off when I try to remove them, so they are stuck in there good.
Hopefully someone here has experience with them and can give a few pointers.

As it is, I'm kind of thinking they will need a lot of heat, so perhaps buying new plugs and welding something to the old ones to get them out might be an option.

There's also a few big hex plugs along the spark plug valley, I'm not expecting those to be as impossible to remove but please let me know if you've dealt with these before to.

My idea to get the head clean include multiple solvent baths, pipe cleaners through the oil channels and any other bore, compressed air, and likely an ultrasonic bath. If that doesnt get everything out then it wasnt meant to be... but if the factory can clean up the casting sand, then I should be able to clean off any blasting media remnants too I figure.

[Power_uP]

I know you obviously want to complete the work yourself, so this is perhaps a last resort, but do you have one of these thread doctor guys who is local?
Obviously the guy in the link isn't going to be local to you, but you may have someone similar who you can ask.

[oldeskewltoy]

I've had them pulled in each head I do set screw, or ball bearing. I let the machine shop pull them because on occasion the plug will strip the Allen inside.

[Ivan141]

I'm pretty convinced that heat is what does the trick from some internet research on the subject. There is thread sealant on the little plugs from the factory, plus they are BSPT pipe thread, so they can get pretty stuck.I intend to heat the plugs with a torch and see if that does the trick. The one that I already buggered a little can have a torx hammered in.
If that doesnt help then it's time to weld stuff to them.

[oldeskewltoy]

(09-17-2023 08:49 PM)Ivan141 Wrote:  I'm pretty convinced that heat is what does the trick from some internet research on the subject. There is thread sealant on the little plugs from the factory, plus they are BSPT pipe thread, so they can get pretty stuck.I intend to heat the plugs with a torch and see if that does the trick. The one that I already buggered a little can have a torx hammered in.
If that doesnt help then it's time to weld stuff to them.

OR drill and easy out type tool

[Ivan141]

Well, I ended up welding some stuff to the plugs, real pain in the ass to remove...