Blown head gasket

I would not. You are destroying the engine. The problem is that the repair for this is not an easy one but it is a very common one. The actual head bolts pull the threads out of the block. The repair involves using a special tool to form new threads and installing new bolts while replacing the gaskets. If the car is in very good shape it may be worth repairing. There is also a method that uses larger studs to replace the bolts and lasts much longer, but it also requires more work.

Oh and the way these fail, no type of sealer or stop leak will works as it is not really the gaskets that fail. It is actually that the cylinder heads are lifting off the block.