[sean]

The 84/6Z4 is notorious for shorting out as are the earlier 6X5 rectifiers. All of these tubes are electrically equivalent but have different bases. I had the 84/6Z4 in a 1939 Philco short out on me once. On sets that use these rectifiers I have been getting into the habit of disconnecting the rectifier tube from the circuit and replacing it with a pair of silicon diodes and dropping resistors. That way you can leave the tube in place for aesthetic reasons. If you decide to go that route I would replace the silicon diodes currently in your set with a pair that are of the same type. 1N4007 diodes are the typical choice for this purpose.