Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

CheeseBread365

macrumors regular
Original poster
Aug 27, 2017
141
13
Ann Arbor, MI
I picked this thing up for free. Ithe worked fine after I installed an os, but later on in noticed a capacitor had been torn off, and 4 were bulging. Is it safe to go on like this?
 

Attachments

  • 1508892331786-594735651.jpg
    1508892331786-594735651.jpg
    1.5 MB · Views: 528
Last edited:
Replacing the capacitors will likely fix it. But not replacing them and continuing to use if can result is permanent damage that will render it unusable.
 
  • Like
Reactions: amagichnich
I've also got an iMac G5. All of the caps look normal except one that is very slightly bulging. Just that one cap makes the whole thing unusable. It boots up fine, but after a few minutes the display gets all jumbled with white lines and kernel panics. I have to unplug it for a few hours for the caps to discharge before it'll boot again.
 
OP, do you have decent soldering skills and equipment? The iMac G5's logic board is a challenging one to recap. You may see if you can scrounge some junk boards to practice on.
 
I unfortunately dont have the equipment

Even with reasonable equipment, don't underestimate the difficulty in capacitor removal from iMac G5 logic boards. From what I've read and learnt, a soldering station is highly recommended, incorporating a desoldering heat gun.
It's certainly an excellent tip to practise capacitor removal first from a scrap board. I did this with a good brand (Weller) soldering iron, and after several attempts found I could remove them ok. When I tried the same with a G5 iMac logic board that I had just removed, the scenario was so different. I failed miserably! I believe this is due to the fact that those G5 boards are not only multilayer but also feature unleaded-solder joints. This makes heat transfer to the capacitor joints difficult to say the least.
In the end I ordered up a set of capacitors from a highly recommended specialist online, and found a repairer with a pro soldering station/desoldering heat-gun to change them all. Cost 25euros - and well worth it! After I reinstalled the logic board, the iMac booted first time, and now forms a pleasant addition to my collection.
 
As boards get more and more dense, component level repairs become increasingly more difficult.

When my dad retired, his office was still running a Wang VS 600(with virtualized terminals on Wintel boxes). They had a service contract, but repairs would often involve them meeting up with the company to exchange boards-the service company wanted the old ones back, and the replacements would often be a rats nest of wires to repair broken traces and other things. I can recall a couple of trips to St. Louis with him to meet a technician and swap boards.

That was done out of necessity, as that was well after Wang was out of business and of course at that point the VS600 was probably 20 year old tech(albeit with no real alternative-they had a long term migration path, but the company they worked with was still working on writing software for them for a newer HP minicomputer. I don't think the Wang was retired until 2012 or so).

You almost need a hot air work station if you want to do component level repairs on modern boards.

Contrast that with early Macintosh boards, where I've used just a bare bones soldering iron and managed to make successful repairs.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.