Author Topic: Quadra 840AV - recap  (Read 45 times)

Offline Syn-Fi

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Quadra 840AV - recap
« on: November 14, 2017, 01:29:40 AM »
hi,

i purchased my Quadra 3 months ago and it didn't seemed to have seen much use and there was no signs of a leaking battery so i put off any serious servicing and just the unit and installed a scsi/ide bridge with compact flash.   Latterly, it would not boot up consistently so i investigated the caps and noticed there was black ooze into traces....especially the ground.  This was confirmed when i started lifting some of the caps off the board, both in terms of black liquid and smell. 

The ground on the Quadra 840av is meagre and so i replaced all the caps and also wired main point where the ground on the pcb goes to the power cable.  The quadra is working fine now.

Use a heat gun to remove the SMD caps and then an iron, with plenty of flux to solder them on - you need some dexterity with the soldering iron.

one thing i would note is that the PSU seems to be running, mildly warm, even when the unit is switched off.  i only noticed this as we get into the Winter months and i checked it with my IR heat gun.  I now switch off the unit from a ganged extension mains distribution panel.

So, if anyone is recapping - shore up the ground too