Either way, the edit to the OP is valid. Silicone lubricants are not ideal for fan bearings and should be avoided.
I am not comfortable with that as a blanket statement. Silicone lubricants are commonly used to lubricate all sorts of electric motor bearings, including fan motor bearings. Silicone-based lubricants have excellent heat-resistant and lubricating properties and are compatible (non-reactive) to many materials used in motors.
but still benefit from cleaning and relubrication.
To me "
cleaning" is by far, the most important, most pertinent, and the most valuable piece of advice anyone has given in this whole 8 page (so far) thread.
Generally speaking, when it comes to lubrication, there are two types of motors. One is designed to be relubricated and therefore, has integrated in the design, methods to do so. For grease, there should be a grease fitting. For lubricants that flow, there should be some sort of access port with a removeable cap. Clearly, these type motors are not found in computers - in part, because they leak. Not good for electronics.
When relubricating (or adding more lube) to motor bearings, it is critical to add the same formula lubricant as required by the manufacturer. This is to prevent the new, potentially incompatible lubricant from breaking down the old, or failing to blend thoroughly, resulting in a new mixture that now has degraded lubricating properties.
The other type of motor is sealed and NOT intended to be relubricated. But industrious, capable users don't always do what product makers intend for us to do. And that's fine, if we know what we are doing and safety is not an issue.
One important point to note (and not forget) here is when fan motor bearings start to make noise, that means excessive wear (which "IS" minor
irreparable damage) has already happened. These bearings (and the channels they run in) are no longer perfectly round or smooth. Cleaning and relubricating will extend the life, but not indefinitely. Relubricating is a temporary solution. Worn bearings will continue to wear because they are no longer perfectly round, or smooth. The noise will return and/or the motor will seize, sooner or later.
The second important point is the same as above. When relubricating a sealed motor, the same lubricant should be used to avoid one contaminating and/or breaking down the other.
Now, back to my point. Computer fan makers never (AFAIK) publish the lubricant's specs, Therefore, when relubricating a fan's bearings, it is critical to thoroughly clean out the old lubricant before adding your new - to avoid such contaminations, incompatibilities and breakdowns. A good scrubbing with electrical
Contact Cleaner and a
acid brush typically works good for that.
Also, thoroughly cleaning out the old lubricant is critical because it has already been contaminated by the "grit" and other particles that, through friction, were worn off the bearings and bearing channels. I mean there's no filter in there to replace, right?
Once thoroughly clean, at that point, IMO, as long as the new lubricant is designed for small motor use, the type of lubricant matters little, if any. You can use silicone based, lithium based, or petroleum based. But not corn or canola based oils.
I HATE FAN NOISE. So when one of my fans starts to grind and rumble, I start my research for replacement fans. In the meantime, my first "temporary" solution to keep me from going insane is to slow down its rotation speed, if possible. If I need more time until delivery, I will peel back the seal, clean and re-lube. But I know replacement is the only real "fix".
Six fans at $20 a shot really adds up.
True but what are the odds all six fans need replacing all at once?
