reverb problem in 66 vibrolux

[blues man]

I'm working on a 66 vibrolux and I just did a complete cap job on it. I'm getting an oddball distortion sound riding on top of the note that sounds like a blown speaker when the amp is cranked in the reverb channel.  I removed the 12at7 reverb driver tube and the problem goes away and the overall sound of the channel sounds much better and it breaks up real nice. I tried 2 more 12at7 tubes and I get the same results. All my voltages seem good. Any suggestions? I changed all the components in the reverb circuit trying to find the problem but no luck. I am also assuming the problem is in the reverb circuit since when I pull the tube the problem goes away. Any help would be appreciated. Max

[blues man]

I just found the problem. The reverb tank.

[phsyconoodler]

It's the reverb tank!

Ah,crap,you beat me to it!