Turn off Hard drive in a Airport time capsule tower

Strongly recommend that you replace the fan. It is readily available. Trying to lubricate the fan will tend to gum things up and if the motor bearings are worn.....they likely are.....the fan will product unwanted vibrations.

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Google "AirPort Extreme Fan" if want more options.

As far as opening up the Time Capsule, most articles do not stress enough that it is very easy to break a connector or tear a ribbon cable in the process, since the Time Capsule tends to self destruct when you try to pull the components out of the case. This what happens when a product like the Time Caspule was not designed for service.

A failing hard drive will throw up drive errors in the Airport Utility.

And I do think fan is possible cause of strange sounds.. you can check the diagnotiscs in the airport utility.. look at the area for thermalinfo as this will tell you if the fan is failing.

Post a screenshot of the ThermalInfo and we can help interpret it for you if you need.

Particularly when it is making odd sounds.. the diagnostics happen every few minutes and is date stamped into the name. Most recent should be last one listed.

If you turned off diagnostics you will need to turn them on.

Are you sure that it is the hard drive that is making noise? It is much more likely that the internal fan is making the noise.

Can you describe the noise in detail?

No matter whether it is the hard drive or the fan that is making the noise, you will have to open up the Time Capsule to get at the components. If it is the fan making noise, you can replace it for about $20.

Apple Service Part: Fan for Apple Airport Extreme & Time Capsule ...$19.99OWCFor most items:30-day return policy

If it is the hard drive that is making the noise, the simplest thing to do is unplug and pull the hard drive out.

The Apple forum moderators will not allow us to provide instructions on how to take the Time Capsule apart, but you can find that information using a web search.

The internal fan tends to produce an intermittent rushing or roaring type of sound when it is clogged with dust. It can also emit a screeching sound if the fan motor is failing.

A defective hard drive normally makes a continuous clicking or clacking noise.......(for not for long before it fails).

Either way, you will need to take the Time Capsule apart to find out what is really making the noise. There is no way to disable the hard drive without physically removing it.

should the fan be replaced if I can purchase it?

Just to add to what Bob has posted.. definitely replace. Fans have a limited lifespan. I don't fix many AC version airports but other repairers report doing high level service like stripping down the fan and oiling the bearings might fix the problem for only a month or two before it starts to make noise or fail again. You certainly don't want to have to repeat the exercise.

Fan is the weak point in this model and is ESSENTIAL to its operation. There is no natural cooling to speak of. The only vent is in the bottom. It is tiny and hot air rises not sinks. The plastic is also very thick and is of course a very very good insulator. With the fan off the temperature will rise to very high levels and damage other components.