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Ruglet

Re-cap gone wrong.

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I recently bought a Performa 450 (LCIII) off eBay as it was my first ever computer and I always regretted getting rid of it. I booted it up and it started fine off the hard disk, but the speaker was making a whining sound. I attributed this to the usual bad capacitors, and when I opened it up there was indeed electrolyte leaking so I proceeded to change them. All seemed to go well, but when I had finished and booted up the Mac, the hard disk drive can no longer maintain constant RPM. It seems to be only getting intermittent power. I went back to check my soldering work (reflowing the solder in several places) and as I did so I inadvertently ripped one of the solder pads clean off the board. Stupidly hoped to be able to re-attach it with a little solder on the bottom, but this has simply resulted in a black mess beneath the pad and it still won’t attach properly. 
 

So I currently have:

A Mac which cannot supply constant power to the HDD

And - a solder pad unstuck from the board, unsure of what it affects or how to fix it and with possible damage underneath it

 

can anyone help me out on what to do next? I am quite a beginner at this, and as this Mac is getting rather rare I really hope to be able to salvage it!

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The LC form factor power supplies nearly all need recapping, so that may be your next project, in order to restore proper voltage to the HD.  For the lifted pad issue, you might get lucky and be able to easily trace the via to a spot that would allow you to solder on a jumper wire.  If not, repairs can sometimes be accomplished, but they are not easy.

 

Congrats on getting your machine.  Hope the repairs go well.

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Every LC power supply I've taken apart so far has had cap leakage, even the ones that still worked. On the plus side they're the easiest power supply to work on in my own experience.

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If your hard drive isn't getting powered, it's almost certainly a power supply issue. I had an LC that was going through this same process and a re-capped power supply solved the problem. I had another LC on which the hard drive wouldn't even power up sometimes. Again, a new power supply solved the problems (as well as a video problem that couldn't be attributed to the main board, which was re-capped).

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Thanks for the replies so far. I finally had time to come back to this project, and here are my latest findings - power supply is a Dyna Comp unit. As far as I have read these are not prone to failing, but I decided to test it all the same. Opened it up,  no visible signs of leakage. Tested the voltage, got +5.3, +11.3, -4.3, all nailed on steady with no fluctuations, as far as I can tell that is normal and indicates no issue. 
 

I managed to source a performa 450 logic board  which was going to waste so I decided to buy it - if nothing else it will be useful to have a spare if I can’t repair mine or for testing if something else fails later on down the line. I thought I had ballsed up the recep but surprisingly this known working board gives the same hard drive issue. I’m starting to suspect a faulty drive. Is this a decent assumption to make? What is the voltage which should be seen going into the drive from the drive power connector on the board? It would be interesting to test if this is normal. 

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I am glad to read this topic, I just got an LC III as well and I have the same problem with whining speakers. I just bought new caps for the logic board and plan to recap as well. Don't have any plans to recap the power supply though. I am using a scsi2sd not a hard drive so hopefully voltage won't be a problem.

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