Old amp blows fuses with no tubes in: fault of rusty PT?

1/30/2006 1:16 AM

Carlo Pipitone

Old amp blows fuses with no tubes in: fault of rusty PT? I bought this 1482 Silvertone amp off ebay. The seller admitted that it blew fuses.   Now I have done a cap job and replaced a few drifted resistors. All the negative lugs of the e-lytic caps are connected to ground, so there should not be a miswiring problem at this end.     PROBLEM:   about two seconds after startup the 1A slo-blo fuse blows. This happens with NO tube in the sockets.   New fuse, same behaviour: about two seconds of life.   The power transformer is rusty outside, both on the black casing and on the laminations (here less than on the case). The screw heads are totally rusty.     How do I check if rust is the culprit?   What else should I check?     TIA,   Carlo