Is this a capacitor leak?

Discussion in 'General Electronics Chat' started by devineas, Dec 18, 2010.

  1. devineas

    Thread Starter New Member

    Dec 18, 2010
    This is from an external hard drive that is not working. The hard drive itself works fine if hooked directly to MOBO. The two images are from the external hard drive and have some off white colored substance in between the capacitor and inductor. Is this possibly a leaked capacitor? Thanks for help.
  2. SgtWookie


    Jul 17, 2007
    The blob of white stuff is an adhesive to keep the inductor (the wire-wound toroid thing) attached to the circuit board. Without some sort of adhesive, the wires would flex and eventually break due to metal fatigue.

    Are you using different cables to connect it to the mobo than when it's portable? If so, I'd look at those cables really closely.
  3. marshallf3

    Well-Known Member

    Jul 26, 2010
    You often find a similar adhesive on electrolytic caps for one of two reasons. In most cases it was put there so it would go through the wave (or other) soldering process to keep it in place, in HV circuits it's there to try and help bleed off the static charge that can sometimes build up on the outer case of the cap.

    The worst case you can run into is the fish based glue that they used for ages and probably still do for all I know. (haven't been in the service industry for ages) Over time that stuff becomes hygroscopic then becomes conductive to an extent but luckily it will usually pop off with an X-Acto knife.
  4. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
    What brand is it? The little boards at the back are small switching power supplies to get the right voltages (12V and 5V) to the drive. I've had several go bad, the drives, not the power supply. A couple big Seagate and 1 small Seagate 1TB external, as well as a Western Digital large size external.

    If yours is one of those, and you have a DMM, I can dig around and see if I still have them and let you know the voltages when they work.

    I find it odd that a 2TB External USB drive is cheaper than a 1.5TB internal SATA drive, inside, it's just a SATA Drive with the USB connector and power supply. :confused:
  5. marshallf3

    Well-Known Member

    Jul 26, 2010
    You can always unplug the drive and run it through some tests on a normal desktop PC.