Woodworm and rot

I'm in the wilds of Nepal - I am constructing a house and bought some intricately-carved antique window frames, but there are woodworm holes apparent. Before re-assembling and fitting these windows I would like to treat them with a preventitive against woodworm and rot, but nobody in Kathmandu seems to sell anything for this purpose - no creosote, nothing. Previously in India I painted old engine oil on terrace planking. This is a treatment that most Indians give to wood, but I have just read on this site that oild engine oil contains acids that break down the cells of the wood! That seemed to be the last option - using something that can be obtained easily. I don't even think linseed oil would be easy to find here

Can anyone verify that old engine oil is indeed a good or a bad treatment, and if it is bad, does anyone know of any effective treatment using common materials?

Thanks

We use a white power that is borax based -- make it into a spray and spray affected areas

I wonder if filling the holes with beeswax would work.

Thank you Eric and John. For the borax-based treatment, does anyone know what is mixed with the borax? I'll try getting beeswax to plug the holes afterwards. By the way, does anyone feel that applying old engine oil would benefit? THAT IS available!