Oil leaking around spark plug 2 &3

Loose plugs, bad copper gaskets, bad thread in head, bad surface on top of heat where gasket goes, bad threads on plugs, bad surface on plug. Take plugs out. Get new gaskets and plugs. Look at mating surface to see if there is a defect. Screw in new plugs without gaskets to see if the surface on the head is square to the hole (there should be no gap). Screw down new plugs with new gaskets to proper torque.
 
That is possible as it’s fairly new from Snyders and first time I took plugs out the top threads broke off. I called and they let me send it back but instead of doing anything to correcting it they just run a tap in each hole which didn’t take care of the broke threads at the top. I called and talked to Mr Snyder and they won’t do anything more. Looks like they taped the head which is their HC head then ground the flat for the plug seat and that left a sliver of a thread and it broke the top thread off. Hate t buy another head but it’s gettin worse to change plugs.
 
It's not really oil coming out,it is combustion by product.It will have a slight creosote smell,and might feel a little stickier than oil.If the plug boss on the head is smooth and flat,and the same with the plug and copper gasket,a missing thread shouldn't be a problem.I've filed off lots of top threads that people cross threaded the plugs and ruined.
 
The gasket is the seal, not the threads. I doubt that having the threads broken at the top would allow oil, or combustion products, to leak out. (However I have been wrong in the past.) Screw down the plugs without the gaskets and then try to insert a thin feeler gauge around the circumference. Try a 0.002 gauge or a 0.001 if you have one.

Carefully examine the sealing surface on the top of the head to see if you can see where the leak is. Also the plug and gasket. If, as you say, they resurfaced the sealing areas on the head, they may be not perpendicular to the threads. Or the threads may not be cut perpendicular to the sealing surface.

A Model T has a pipe thread for the plugs and I used to use Teflon tape to seal them. That could be a fallback fix for you. On my Model A plugs, I use a copper bearing anti seize paste. The anti seize is also a good idea for any plugs, especially ones that screw into an aluminum head.

If you find that the head is defective, try again to get a replacement from Snyders.

Is it possible that the plugs are at fault? Perhaps the threads or the relief where the threads end are not correct and that caused the top threads in the head to break off.

Another thing to try are two gaskets for each plug.
 
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