Ampeg V4B smoke

[hbann]

Smoke came out of my 1977 AMPEG V4B, I will try to describe the problem:

I didn't use it for so long and when I finally did,I noticed it was WARMING UP A LOT so I attached a mini fan and kept using it because it sounded normal.But some time later...each time I pressed the power switch,small sparks jumped over from inside the panel through the "slots" around this switch and smoke came out of it.
Today,I opened it and noticed that part of a shielding is unwrapped and spreaded.At photo #3 please notice that I moved the shielding away just a little just to show exactly the location of it.
Maybe this "aluminum foil" touched other parts and this caused the amp's failure,I just don't know...
Thanks in advance for any help and comments you may give.

[R.G.]

Smoke came out of my 1977 AMPEG V4B, I will try to describe the problem:

I didn't use it for so long and when I finally did,I noticed it was WARMING UP A LOT so I attached a mini fan and kept using it because it sounded normal.But some time later...each time I pressed the power switch,small sparks jumped over from inside the panel through the "slots" around this switch and smoke came out of it.
Today,I opened it and noticed that part of a shielding is unwrapped and spreaded.At photo #3 please notice that I moved the shielding away just a little just to show exactly the location of it.
Maybe this "aluminum foil" touched other parts and this caused the amp's failure,I just don't know...
Thanks in advance for any help and comments you may give.

Please try not to be offended by the advice.

Smoke and sparks coming out indicates that this is a problem which may well involve fires and electrocution. Your description makes it clear that you will not be able to fix it yourself. Therefore,

=> Get this amp to a qualified service tech before you turn it on again! <=

Yes, it is serious, and no, you will not be able to fix it by doing something trivial. Do not endanger your life and the lives of others by messing around getting advice on the internet from somewhere around the planet.

None of us know exactly what went wrong inside it, either. Some things lend themselves to remote/internet advice. This does not. The risk of real damage to you and your amp is too high.

[hbann]

Correct advice

You're right and I surely don't have the intention to fix it myself,what happens is that I live in Brazil and I'll be in the U.S soon but unfortunately will not be able to take the amp w/ me 'cos it's too heavy but could bring a replacement part if necessary.
Here,I took the amp to 2 technicians(when it was warming up)but both said this was perfectly normal and I insisted it wasn't(they charged me in dollars for the inspection)...I'll try another repair person before I leave but I'd like to have an idean in advance because many of them here use to state: "put it away it's too old but if you decide to sell it call me...."
Thanks for the correct advice,we shouldn't be curious and mess with this kind of stuff!
Best Regards

[Diablo]

It looks like one of your capacitors exploded. At a minimum, they're going to have to replace that one, and it's a good idea to have them replace all small electrolytic capacitors in the amp. There's not too many of them, they're cheap, and likely to go bad after many years. It's especially important to change out the capacitor in the bias circuit. Without a good bias voltage supply, you'll have no end of problems.

[hbann]

V4b smoke fixed

Hi,
A technician easily FIXED it!
He showed me that the problem was at the AC outlet at the rear panel.I was at his side all the time watching attently as he explained that a wrong voltage there caused the 047 600v capacitor to explode...then,he disconected the AC outlet's wires and soldered it direct to the circuit and in few minutes,I was coming home with my amp(which still warming up a lot but I'll replace the tubes soon and that must solve it)working again.
As I mentioned,I used to plug a small cpu fan in it and "surely the voltage plugged in it was 220" the tech said.

[hbann]

Thanks Diablo

Thanks for helping Diablo I'll have the small capacitors changed as soon as possible.I saw your post after I took it to the repair shop...