Is this a dead output transformer?!?

[wcrankshaw]

It's measuring zero resistance between the secondary 8ohm tap, and common, and zero resistance between both secondary taps and chassis. Please confirm this for me if you know the answer. This is of course accompanied by the fact that there is no output.

[52 Bill]

The resistance of the secondary winding is usually so low that it will read as a dead short to most meters.

One side of the secondary is wired directly to chassis ground, so it would look like the other taps have continuity to the chassis as well.

What kind of amp is it?

[wcrankshaw]

ac15 reissue

[jmaf]

Like 52 bill said, most ohmmeters will report a short.

The most practical way to test for a completely dead transformer is to hook the 8 ohm side to an actual speaker and quickly tap a 9V battery to the high voltage primaries taps and CT. The speaker should pop.

Don't keep the battery in contact too long, just tap it, DC is not welcome there.

This only tells you whether you've still got a somewhat working OT, more ellaborate tests are needed to tell if you've got shorted turns or major core leakage, etc... Hope this helps.