torque limit on frozen water pump bolt

Had same problem. Heat ,oil ,and then the 3/8 impact worked for me. Ended up replacing timing cover and bolts when i put it back together. Everything was corroded bad. Be sure to use silicone on the bolts that thread into coolant jackets when putting it back together. Anti freeze raises hell with aluminum. WHO SELLS KROIL? NEVER HEARD OF IT. WANT TO GIVE IT A TRY.