W5M Power Xfrmr Question

[John Schmitz]

I recently completed rebuilding a W5M Mono Block and am extremely pleased
with the sound quality of it. There seems to be just one problem. After
running for several hours the power transformer gets HOT. I mean really hot!
It seems way to hot for normal. All the supply voltages and ripple are very
good. Sound remains outstanding even when the transformer is excessively
hot. I tried letting it sit on, idling with no input signal for several
hours and it still occurs. I thought maybe there might be shorted windings
internally but voltages are right on. I calculated the idle current through
the finals using ohms law across the 330 ohm common kath resistor and come
up with 97milliamps, this seems reasonable. My next step is to measure
secondary current flow by inserting an amp meter in the ground return center
tap of the secondary. I'm expecting to see about 140ma, but I have not done
this yet. My question is:

Is the power transformer in these amps a weak point? Is it normal for the
transformers to run so incredible hot or do I have a tired old transformer
that has seen better days.

John Schmitz

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