Mac Classic loud hum from PSU when attempting to start

[Rick Dangerous]

I will admit it's been about five years since i fired up the ole' classic.

When I tried to last night, there was a disturbing loud humm (electrical sounding) coming from the PSU area.

I opened her up and all the boards are good, no exploded caps or PRAM batteries that I could see.

Of course I don't know much about CRT tubes or PSU's so i left those alone not wanting to electrocute myself.

Has anyone encountered this before?  I do have a local electronics guy who is a wizard with soldering and electronics and has been doing it professionally for 35 years.

If this is something that could be easily fixed I would like to do so before salvaging parts and going the Macquarium route. 

Thanks!

 

[bibilit]

The Classic is known for failure in the PSU area.

Never seen exploded capacitors, most of them are leaking heavily instead...

Around 10 to be replaced.

 

[Rick Dangerous]

So likely capacitors in the PSU then?  Thanks again. 

 

[BadGoldEagle]

bibilit is right. On the Classic, the caps are not of the explody type, but they are definitely leaking. I just recapped a TDK PSU from an LC II and the caps were completely shot.  Sometimes you can't really tell if they're leaking or not before removing them...