Extremely bad WTF syndrome in 1973 Super Reverb

[booj]

I've never seen fiberboard conduct so badly as to give me 8+ volts a half-inch away from the B+ connection. It's everywhere on the board. 1/2 volt up to 8+ volts.
The question is, is there anything that can be done? Leave it out in the sun to dry? We are in the middle of a heat wave here.

[Enzo]

In my experience, it isn't that the board is wet, but rather moisture has adsorbed into the waxy surface. Since the alternative is to replace the board and transfer or replace the parts on it, why not try to save it. I had tried solvent cleaners and other things, but the one thing that always worked for me was my heat gun. I start at one end and slowly work my way down the board. I can watch as the surface changes appearance - if I had to describe the change it would be it gets a little less shiny. And once it makes that change, the problem is gone. It may not always work, but it has been succecssful for me.

[booj]

Thanks, Enzo. After I made the post I realized it's been stored in a shed for at least a week where the temperature hits 115 - 120 degrees every day. I'll try the heat gun approach. The amp works fine. The controls are a little noisy is all. But.. it came in with a blown fuse. I changed out the bias cap and replaced the screen resistors which were way off. Other than that and a few bypass caps it's been re-capped previously. My fear is that the bias is going to be affected by the board leakage, and may be responsible for the fuse failure. I'll post the results.

[Gtr_tech]

Fender disease.....

[booj]

I used the heat gun approach and heated an area of the board until the residual solder resin around the eyelets would start to bubble. I did the whole board that way. After letting it cool down about 1/2 hour, I found on average about 1/10th the residual voltage it had before. Really a definite improvement. the amp is much less noisy. Useable now. Thanks again.