Arcing output tube

[hesamadman]

I have a fender deville that originally had a blowing fuse. Had the original Fender tubes installed. First assumption was output tubes. Put in an old pair I had and fuse held fine. Played fine. No problems. Ordered a tube replacement kit for that amp. Apex matched JJ's. Put them on, turned bias pot counter clockwise to max -dc bias voltage. Then biased to 63mv. I had one of the output tubes arcing internally every so often. Was also having a slight bit of trouble stabilizing the bias. It finally settled down and hasnt done it in a while. I swapped the 2 output tubes around. So the arcing one was on the left now instead of right. Have not had the problem since but I dont want to give my buddy his amp back if this could have been manufacturer defect. No signs of wear or arcing on tube sockets either. Should I send tubes back or check something else?

[sluckey]

Definitely sounds like the tube. But it's settled down and you may never see that arcing again. Murphy says it will burn up as soon as you give it to your buddy. 

[hesamadman]

Definitely sounds like the tube. But it's settled down and you may never see that arcing again. Murphy says it will burn up as soon as you give it to your buddy. 

ha ha ha That had me laughing pretty good. And you're absolutely right about that.

[Jack_Hester]

I had a power tube to start arcing right after I set the Bias using my adapter, and re-installing the tubes in their sockets.  Seems the adapter pins were very fat, and sprung the tube pin sockets.  The tube pins were way smaller than the adapter pins.  Tube started arcing right away.  I powered it all down, bled the caps, and snugged up the pin sockets.  Put the tubes back in and powered it up.  No more arcing.  Amp and tubes still working just fine. 

Jack