🚀 go-pugleaf

On Tue, 28 Apr 2009 04:05:53 -0700 (PDT), pg
<penang@catholic.org> wrote:

>One of the company PC is located in the warehouse area, and that place
>is very dusty.
>
>So dusty that a lot of grime have built up in the heatsink + cooling
>fan, and the CPU temperature is rising as a result.

What is the grime comprised of exactly?  If it is just a lot
of dust, it can be blown out or use a small paint brush.  If
it is gunk like grease from a kitchen, tobacco smoke, or
other gunk like industrial residue then you may need a
liquid cleaner for best results (having first removed the
fan, and possibly heatsink too depending on how bad they
are).


>
>In the process of cleaning the PC, I disassembled the cooling fan +
>heatsink assembly from the CPU, trying my best to clean away all the
>dust and grime stuck on the heatsink and the cooling fan.

You make it sound really bad.  If there is that much dust
you may have an environmental problem, that much gunk and
dust in the air is bad for the users as well as the computer
so I would suggest a room air cleaner, more frequent
vacuuming or sweeping, and if this isn't enough then also a
case air filter or even a different case if the one used
cannot accomodate filters.  

Many filters designed for screwing onto a fan can be put
over fan grills in a case even if there is no fan, you
simply need to use the right sized bolts and nuts (and
washers if needed) instead of coarse threaded fan screws.
Beyond fan-specific filters even a piece of foam or a
slide-in panel for a wall air conditioner filter, or a piece
of panyhose, whatever, can be taped or screwed onto air
intake areas.  

Just keep in mind that to whatever extent the filter is
effective it will reduce airflow some, and even more if not
cleaned out on a timely basis but that may be better than
having to clean dust off everything inside the system.

>The cooling fan / heatsink assembly is joint together by 4 washer type
>of stoppers (located almost at the half way down the 4 screws) and I
>can't find a way to separate the fan from the heatsink.

I'm not quite clear on what you mean, what make and model of
heatsink is it?  Typically you either take the screws out or
there are pressure clips you retract away from the edge of
the 'sink that they latch onto.


>This resulted in the THICK LAYER of grime and dust that are stuck in
>between the fan and the heatsink to be totally inaccessible.
>
>I tried my best to clean them out but couldn't.
>
>If only I can separate the fan OUT from the heatsink assembly ....

If all else fails, take some good pictures and post on an
image hosting site then link to them here.


>
>So, to the hardware gurus here ---
>
>1. Is there a way to take out the fan from the fan/heatsink assembly,
>without breaking anything?
>
>2. If the answer to #1 is NO, then, is there a way to clean out the
>grimes that stuck in between the fan and the heatsink?
>
>Please advise.
>
>Thank you !!

There are many ways to clean it out.  One thing you do not
want to do is get any liquid cleaner all over the
motherboard so leave the heatsink outside the system if
liquid is used.  Contact cleaner or petroleum solvents
should not be sprayed onto the fan because they might get
into the bearing and foul the lubricant.  With types that
dry residue free and if the bearing is all-sleeve instead of
ball bearing you could, if it came to it, relube the bearing
when finished but it's easier to just avoid the  situation.

If you do it carefully you can even brush hot detergent
solution onto the dirty areas then rinse it off, shake out
excess water, then let it dry for a day before reinstalling
it.  The key is to work quickly and not overapply the
solution or over-rinse because you want to minimize if not
eliminate either liquid getting into the bearing though it
is worst with a ball bearing.  Some might theorize that this
will damage the fan but as of yet I have never damaged one
doing this and have had cases where some really bad caking
of concrete dust had to be removed (I had already replaced
the fans in those systems but out of curiosity wanted to see
if the fans were salvageable, which they were but due to how
fine and abrasive the dust was I also had to pull the whole
blade assembly out and flush the bearing then relube it too.

Point being, many things are possible if you are mindful of
the effects of your cleaning method.  Most often the dust I
encounter only needs a paintbrush to remove it, and it's
cheaper than the ridiculous price of canned air.  

Either way, if a heatsink can be assembled it can be
disassembled, look it over some more and see where the play
is in the fan mounting to decide what to do next, just don't
pull on the fan blade or center hub so as to avoid
potentially cracking the blades or damaging the bearing,
apply all force to the frame instead and take out any screws
that could be holding it down.