Computer fan noise and maintenance

[Fizzycapola]

I thought I'd ask. Fan noise, degradation in increasing audiable levels through
their lifetimes aswell as the electrical disturbances they can cause. As an
electronics and engineering novice maybe someone could help me in a better
maintenance regime than my current one of hoping for the best.

So I have these questions:

How can PC fans be maintained? (bearings, lubrication, cleaning off dust & particulates)

How can PC fans be prevented from causing electrical interference?

The fans I use are double ball bearing & sleeve bearing. Connected to 12v
rail and onboard connectors.

Excerpt from an offsite link, link provided by willawake

Fan control output
The pulse width modulated output of the fan controller lacks noise suppresser, which should better be used if you use poor DC fan. Switching current to an inductive load generates sevier high voltage noise.
A snubber of 100nF to 1uF MLCC with 100Ω in series will be enough.
It added one snubber of MLCC of 1u/16V and 100Ω each between Vfan and GND pins of fan connectors.

[davmax]

Re: Computer fan noise and maintenance

How can PC fans be maintained? (bearings, lubrication, cleaning off dust & particulates).

I have had long life with fans by using a fairly stiff paint brush to remove the dust on blades and body. Compressed air is useful but a dirt film often remains. I believe some use water to remove this film, there is an obvious need to ensure the bearings do not remain wet. For lubrication I use a synthetic oil 10-50 grade, it is thin and will not gum up or evaporate. Oil is applied by removing the circular sticker on the non moving side, gaining access to the bearing. About two small drops is the limit. I use a micro oiler with a hyperdermic needle diameter oiling tube.

How can PC fans be prevented from causing electrical interference?

What interference is the concern? Degraded computer performance or radiated radio interference?

Fans may generate pulses but in general these are removed in computers. Those connected to the motherboard and the power supply leads encounter filtering. eg fans creating noise on the twelve volt output of the power supply will not affect components down stream due to electrolytic cap filtering and possibly switching power sources down stream (that contain considerable filtering).

It would be nice to have examples of fan noise impact that has been eperienced and identified.

[willawake]

Re: Computer fan noise and maintenance

the ideal way would be to use quality fans like these ones and preferably not get them dusty in the first place by using dust filters.

i have had mixed experience with using oil on small fans, sometimes the noise is gone but starts up again later. perhaps my oil is no good?

funny how a fan can be working without noise for a long period of time like a server on 24/7. then you shut it down and oops a noise starts.

[Fizzycapola]

Re: Computer fan noise and maintenance

At the moment I use 2 x Silent Eagle 1000RPM. 1 x Akasa Ultra Quiet 1800RPM intake. 1 x 120mm Akasa Ultra Quiet 1400RPM outlet.

Silent Eagle
Akasa Fans

Theres no immediate issue with the fans. I was just curious to how expertly
maintain them better.

[Per Hansson]

Re: Computer fan noise and maintenance

I use mist oil, like used in industrial compressed air systems to lubricate the equipment that runs from the air...

[davmax]

Re: Computer fan noise and maintenance

How long does mist oil last? I have found a need to be cautious about oil that can evaporate. I have seen CRC used and this soon evaporates.

[kc8adu]

Re: Computer fan noise and maintenance

funny this fan lube subject came up.
temporarily fixed a bad fan in a hurco bmc40 by feeding it a drop of way lube.
got funny looks from the operator but it will run long enough to get a new high quality fan.

[linuxguru]

Re: Computer fan noise and maintenance

Slightly tangential, but I found that the Thai or Chinese-made NMB KL3110-series fans are great, inexpensive replacements for PSU fans.

[Per Hansson]

Re: Computer fan noise and maintenance

How long does mist oil last? I have found a need to be cautious about oil that can evaporate. I have seen CRC used and this soon evaporates.

The fans I've used it on still all work just fine... (and they did not before)

[gonzo0815]

Re: Computer fan noise and maintenance

I recently refurbished ;-) an AC Silent TC fan by adding a bit of motor oil solved in some WD40. The fan dos not move easily. It stoped instantly, if pulled by hand. After lubrication it behaved like a new one. The WD40 will fore shure evaporet fast, but the 10w40 motor oil will probably last for decades. If not, the onwer has to by a new one. I dos it out of curiosity, it was not the main problem i had to fix.

[tazwegion]

Re: Computer fan noise and maintenance

I used some suspension dampener oil from my R/C Tamiya Hornet kit... the fan is still going strong & silent

Sometimes... replacement fans can be hard to source, @ least re-oiling a fan can buy you some additional time

[Tom41]

Re: Computer fan noise and maintenance

One time when a fan in my server PSU started grinding, I took the label off and put a couple of drops of oil on the bearing. Started it up again, perfectly 'silent' again. Although it may need oiling again in the near future, it's beginning to rattle...

[Fizzycapola]

Re: Computer fan noise and maintenance

Ok I "topped" up the oil in one of my fans to experiment. I won't say what I used though but you can imagine. Lets just say it grows in Italy, working good!

[PeteS in CA]

Re: Computer fan noise and maintenance

Did you toss in some minced garlic?

[Shroomie]

Re: Computer fan noise and maintenance

Careful Pete, you'll make my Delta 120mm exhaust hungry...it's already grinding a bit, so I'll have to oil it soon. Guess it's done fine so far, seeing as I pulled it out of a 1999-vintage HP Netserver (dual P3) that got knocked off by a power surge...

I'll try these suggestions, thanks guys! I'll let you know how it goes.

[bgavin]

Re: Computer fan noise and maintenance

While at IBM, I learned that dust is the cause of most machine wear, and oil attracts dust. We got longer life from components such as fan bearings by keeping them free of dust and oil.

Replace your fans on regular intervals, same as brake pads or tires. Fans are just service parts, like car parts.

I rotate my clients' hard drives every 3 years, and (thanks to Badcaps.net) have started rotating power supplies on 3 year intervals.

I have great luck with Panaflo fans. They have a sealed, oil filled bearing and run very quiet. I have yet to have one make noise or fail. I run the 80mm U12 series on Alpha CPU heatsinks and get an 8~11C delta.

The fans that die most frequently for me are Antec 80mm case fans.

[gdement]

Re: Computer fan noise and maintenance

The replacement need depends a lot on the quality of the fan. I guess in some large-scale situations it's easier to replace the fans on a regular schedule. Another approach (but maybe not worthwhile on a large scale) is to keep tabs on the fan speed and CPU temperature. You can replace the fan once you notice it slowing down, and clean the dust if the CPU temperature has risen. Tracking the temperature saved my sister's computer - it turned out the PSU fan was dead, that thing was baking and yet even the PSU survived.

I agree with linuxguru that NMB seems to make good fans. If I'm not mistaken, I believe that's the brand of 92mm fans in my 1998 HP Kayak. They're loud but they've been that way since I got the machine a few years ago, I think it's just in their nature.

My oldest good fan is a small 40x20 (maybe 50x20, not sure) CPU fan which I took from a 1997 Packard Bell. I'm using it on a different Pentium machine. It's by far the most impressive life I've seen from such a small fan. Branded PC's seem to have reliable fans in them to save the manufacturer from service calls.

[tazwegion]

Re: Computer fan noise and maintenance

While at IBM, I learned that dust is the cause of most machine wear, and oil attracts dust. We got longer life from components such as fan bearings by keeping them free of dust and oil.

I'm curious has anyone tried a dry lubricant like graphite powder (or the superior) Molybdenum disulfide powder (Chemical symbol=MoS2) to lubricate these case fans?

[willawake]

Re: Computer fan noise and maintenance

or astroglide

[bgavin]

Re: Computer fan noise and maintenance

Isn't Astroglide used when mycoxastickin?