Can you just drill out a broken valve stem and replace it?

Drilling out a broken valve stem is possible, but it requires precision to avoid damaging the valve seat or surrounding components. After drilling, you would need to tap the hole for a new valve stem or insert a suitable repair. It's essential to ensure that any debris from drilling is thoroughly cleaned out to prevent issues. If you're not experienced, it's advisable to consult a professional mechanic for this repair.