On Tuesday, 23 December 2025 16:01:37 Greenwich Mean Time Dale wrote: > Michael wrote: > > On Tuesday, 23 December 2025 02:12:37 Greenwich Mean Time Dale wrote: > >> P. S. I had to replace the fans on my CPU cooler. I had a power outage > >> the other day and when I booted back up, one fan made a little noise. I > >> figure the bearings are running dry. I ordered two replacement fans and > >> put them in today. I can't figure out how to take that old fan apart. > >> I usually take old fans apart and put a few drops of oil in them to use > >> them for less critical cooling. CPU fans always get replaced. No idea > >> why that fan went out so soon tho. I don't think it is even a year old. > > > > Some older/cheaper plain sleeve bearing fans could be oiled to keep them > > going for longer. You'd peel back a sticky label on their top and pry > > open a plastic dust cap - assuming they were expensive enough to have a > > dust cap fitted. A drop or two of very low viscosity oil would re-wet > > the bearing surface and it will thereafter carry on spinning quieter and > > faster. > > > > The modern sleeve design of the Fluid Dynamic Bearing (FDB) variety is > > typically sealed and needs no addition of oil to keep it going. This > > assumes you didn't buy some alibaba discount 'special' whereby the > > manufacturer was economising on every oil drop on the assembly line to > > cut costs. The shaft on the FDB construction may have magnetic > > support/centralisation, is secured with a lock washer and the bearing is > > sealed to stop dirt from going in, or the oil from evaporating too soon. > > If you try to pull off the fan from its armature by force you will most > > likely break it, but YMMV. > > > > Even a plain sleeve bearing should have the best part of 3-5 years life > > depending on temperature and vibration/orientation, before it starts > > rattling. I suspect yours was poorly manufactured. I want to think > > reputable manufacturers of expensive kit would be interested to > > investigate the failure mode of this fan bearing, so you could try > > RMA'ing it. > > I've done the oiling thing numerous times. That fan tho, has no bearing > access at all. I checked both sides. It's solid plastic. I also can't > pull the blades off either. It seems that this style of fan once put > together, locks into place and can't be taken apart or have a way to get > to the shaft/bearings.
Yes, as I've mentioned above the spindle on FDBs is locked in place with a locking ring/washer and the end cap is usually moulded or ultrasonically welded to stop dirt going in and oil leaking out. > The fan that was making noise is a Thermalright 120mm, gray in color and > a 4 pin connector. I've never seen one that I couldn't peel that > sticker back and not be able to oil it a bit. Seems they figured out > what we doing instead of buying new fans. ;-) The fans you can peel off the sticker and add oil yourself, typically have plain sleeve bearings. As far as I can tell the Thermalright 120mm CPU fans have the Sony FDB fans in them and they are sealed. If you take them apart you'll break them, potentially irreparably. > I use the thinnest oil I can find. I used to use some oil that I use on > firearms. It was thin and some of the slickest stuff there is. A > couple drops goes a long ways. Then I found 3-in-1 oil made just for > motors. Fairly thin and made for motor bearings. I admit tho, when I > oiled the fan motor in my fridge, on the freezer side, I used the oil I > use in firearms. It can handle cold a lot better and it is cold in the > freezer. That was a few years ago now. Still running good. 3-in-1 oil, or even thinner(?) sewing machine oil, or perhaps fully synthetic 0W-8 motor oil will work nicely, as long as the sleeve bearing is accessible. Since this Thermalright fan of yours failed so soon, I'd be minded to RMA it.
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