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ian field[_2_] ian field[_2_] is offline
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Default Electrolytics question


"Arfa Daily" wrote in message
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"Eeyore" wrote in message
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Meee wrote:

I was wondering why vertical mounting electrolytics have like an
indented cross on them.


To release the pressure and gunk under fault conditions (or bad
manufacture).


The reason I ask is because there's 4 largeish
one around my CPU on the motherboard and they have all split open,
along the indentations.


Oh dear.

A: How old is it ? (from date of manufacture)

B: Can you read what brands they are ?

C: Has your PC sharted behaving strangely yet ?

D: What brand mobo is it ?

E: Replace ASAP with well-known brand, low ESR (switching) types.


As Graham says, but be aware that unless you are a *very* experienced
solderer, and posess the right desoldering equipment, you will struggle to
do the job. These are some of the very worst bitches to get out of a
board, that you will *ever* come across. And then some.

Arfa


They certainly can be difficult, an absolute must is an iron with sufficient
power to heat the joint through quickly (DO NOT use one of those soldering
guns that passes low voltage/high current through a solid copper element -
they induce destructive currents in the PCB traces!).

Usually the 2 wires can be eased out by tilting the capacitor as one of the
solder joints is melted and then the other until its out.

Clearing the holes also isn't easy, solder wick won't do it you need a
solder sucker and a lot of practice getting enough of the iron tip on the
tinned pad and still leave enough gap to suck the solder through - you will
probably have to go at it from both sides too!

Once or twice out of sheer desperation I've heated the through hole and
swatted the board on the edge of the bench to knock the solder out, but this
has a real risk of breaking any crystals on the board!