I have a 79 beetle and the engine does not turn over. I put a wrench on the crankcase and still did not budge...didn't go super hard. I heard if you put marvel mystery oil in the cylinders it may free it up....Any other options than ripping the engine down and rebuilding???[]

 

You got it, Marvell Mystery oil down the plug holes. If you can, tip it to one side, fora day or so, then the other way so the oil gets into the rings well. I don't gather that impacts are good. If you had the sheetmetal off it it, warming the jugs would not hurt.

Chances are if it froze like that, the bores are going to be in tough shape so a rebuild might be in the cards anyway. But if it frees up, you can always run it until it does have problems.