Quadra 840av - rotted traces

[AlpineRaven]

Good morning all, 

I just picked up Quadra 840av with 2x SCSI cards, 72mb RAM but no hard drives as the seller didn't know what it was on them and wanted to keep them, I knew they have notorious cap leaks in those and I am up for challenge to rebuild it. I haven't yet cleaned it up/wash/remove/wash and recap at this stage typing this.

First of all - it does not power up at all, the PSU is working. Upon closer inspection I can see rotted traces in several areas of the board - I haven't yet used my multimedia tester (as its in my work's car at the moment and it was too cold to go outside as last night it was 5°c)

I just wanted to hear from others how you revived yours? Looks like I will need to solder small wires where the rotted traces are to wherever it needs to go - any pointers/tips with Quadra 840avs?
Thank you once again

Cheers

AP

 

[360alaska]

I bought 3 840AV boards and so far have only been able to make one work, some boards will boot with bad caps but 840AV isn't one of them, 840AV needs good caps to boot. Many times, traces that look awful still have continuity, best to replace the caps and see what changes, then go after traces, and then if you still can't find anything go with the dishwasher.

 

[Byrd]

Consider the 16V 47uF caps to be the worst in quality and have leaked everywhere; on one of of the more complex and exotic boards Apple made in the day

I'd manually clean the board first with isopropyl alcohol spray, or electronic solvent cleaner, see if any life, then recap the lot.  See if any further signs of life ... then dishwasher.  

I recapped mine some years ago but never cleaned the board properly, causing many quirks/crashes/power issues.  Redid the lot and it's all good now, good luck  

 

[AlpineRaven]

Result...

It works!!!!! including sound, SCSI, everything works... I had to crack a bubbly before hehe...

This is a good one and proven that I have recapped properly, carefully cleaned etc.

Cheers

AP