Opening on the underside... i put isopropanol in it and worked it... hope it works

 

It got much better but did not disappear completely.
I'm leaning to putting the amp chassis together.. have played a couple of more hours... works great.

So most likely it was a bad solder joint which made the problem with the burned output transistors?
Since it was the only thing i performed before installing new outputs and tested again...

 

Hello,

the welds are very important on this SU-VX800, happy for you if it is finally solved because it will have made you see the guy ...

For the potentiometers I drown them in KF-F2 (or any other cleaner for electrical contact) and once completely dry I then put a drop of petroleum jelly on each of the tracks and they work again as on the first day.

 

It may be a good idea to simply go through the entire circuit board and resolder every connection with a good grade of solder. I did have to do that for one Kenwood stereo amplifier that had mysteriously stopped working. The poorly soldered area of the board where the failure had been was not easily accessed, so getting to it was a bit of a challenge, but it was the only actionthat got the amplifier working again.

 

I'm very happy it finally works.
A special thanks to MrChips and JoeJester who has guided an amateur through this, and everyone else who has contributed to this thread! It was possible because of you guys.

Regarding the output transistors, should i replace the possible counterfeit outputs on the RIGHT side and replace them with Toshiba's like it's on the LEFT side.... or should i just leave it?

 

If it is working I would leave it alone. If the replacement transistors fail then you know what to do.

 

LEFT channel is playing a little louder than the RIGHT channel, i guess it is the final adjustment in the manual wich i haven't touched yet.

I did a final mod for some cooling of the hot spots before i put it together..
Operating temperature close to 100 degrees celsius can't be good.
Nothing fancy but it works good.

Time to put some better speakers on i guess.