Two days ago I got woken up in the middle of the night by some noise that sounded like somebody was trying to break into my home. Or so I thought in my still half-asleep state. Left my bedroom rather cautiously to check things out, only to find no problem anywhere. Then, while I was standing in my hall, I heard it again. And nope, that wasn’t people trying to break in, but actually a noise coming from the stone-age server that runs this web site. And it sounded pretty nasty to boot. And all that at 02:00 am in the middle of the week… Hah. So what’s happening here? One of the Delta Electronics WFB1212ME-R00 fans running in the machine is experiencing bearing problems. Something like this has happened not too long ago for the unit cooling the CPU & RAM thermal zone compartment. Back then I managed to repair the fan, as I [described in detail here].

This time, the affected fan is one of two intakes feeding the PCI & system board thermal zone and the additional internal fan for said CPU & RAM compartment. Since there are two intakes right on top of each other, there is actually some redundancy there. So this time it isn’t critical, like the CPU & RAM one was, resulting in a thermal trip and lockup of the server two years ago.

So I took a pair of scissors (first thing I could find), opened the server up and rammed it right into the fan after getting it to spin down and stop fully by carefully pressing against the underside of its shaft. This isn’t actually a problem as these special types of fans won’t constantly attempt to spin up, so there’s no overheating issues. The electronics simply briefly attempt a spin up every few seconds and stop immediately if it’s stuck.

 

I did this (not pictured ) because the bearing had started to wobble somehow, and every 20-30 seconds the blades would violently hit some metal parts of the server’s case as the whole rotor lifted off for several millimeters. This also resulted in the fan failure reporting LED constantly going on and off again. Might be the circlip locking the shaft’s axle into the casing that’s broken, not sure yet.

Next weekend or the weekend after that there will be a brief downtime for XIN.at, in which I will attempt to repair this newly failed fan as well. If it’s not possible, it will be replaced with one of the spares I managed to collect in the meantime.

This one has so far made it to ≈30 billion revolutions over the course of about 26 years, exceeding its rated continuous runtime of 8 years by a factor of 3.25×. Not too bad I’d say, but I’m guessing since two of them have now hit their limits within the past 2 years, I might see more failures from now on. We’ll see.

PS.: In case you’re wondering why I’m not replacing them with newer fans: It’s not possible. First, they have physically different 3-pin plugs and second, they use the third pin for a special failure signal instead of for fan speed.