Remove the rectifier and power up slowly with a variac (if you have one) while measuring current draw. Use a dim bulb tester otherwise. If the current is still high, the power transformer is bad, or there is a short on the filament line.
Johnnysan has the right idea. There is obviously a short somewhere. However, you can start at the other end too. Disconnect EVERYTHING from the line cord. Then add each item one at a time. It could be a shorted cord, solder bridge, wire connected wrong, etc. Always start a one end and methodically go one step at a time. I had a transformer that kept heating up. I started at the rectifier and puzzled about it for days. I figured the transformer was bad and went to toss it. Turned out the resistor in the filter section was barely touching the edge of the tube socket. A little heat shrink and I was good to go.
Terry