2017 iMac fusion drive clicking after failure: Is it a risk?

The clicking of the hard drive will likely get worse. @Old Toad's suggestion to erase the physical Hard Drive is about your only option to limit your boot issues without a costly repair to remove or replace the internal Hard Drive.

Here is an Apple article with instructions for erasing the whole physical drive (I'm providing an archived version courtesy of the Internet Archive since I think that older version is easier to understand than the current version since the older version also includes a picture).

https://web.archive.org/web/20250909095655/https://support.apple.com/guide/disk-utility/erase-and-reformat-a-storage-device-dskutl14079/mac

FYI, erasing both physical internal drives will completely break the current Fusion Drive setup. If you have an older iMac which includes a 120GB internal SSD, then you would still be able to use that internal SSD for extra storage.

I would go a bit further and configure macOS to prevent automatically mounting the erased Hard Drive which should minimize macOS trying to access the failing Hard Drive during normal use. Follow instructions in the following article to configure macOS to prevent automatically mounting a drive when booting macOS:

Prevent a volume from mounting at startup - Apple Community

The fusion drive is actually made up of two drives, an HDD and a small SSD. The HDD is the drive that is failing and making noise. Give the 2017 iMac's age and inability to run later macOS versions, it is not worth to pay for a repair.

Short of disconnecting or having the HDD replaced:

1) go to System Settings > Startup Disk > set the external SSD as the Startup Disk.

2) open Disk Utility and try erasing the Fusion Drive if part of it is recognized.

3) live with the noise at startup and save up the fund to replace that iMac.

if that 2017 is worth your time -- try calling around for SATA HDD replacement Quotes to install SATA SSD -- it takes about 30 minutes -- I would recommend a Samsung 970 EVO SSD replacement -- you would also get benefit of blowing out the dust from a 2017 iMac

I would not 're-fuse' the new SATA SSD with the Apple NVMe SSD (just Erase it and use it for fast storage)...

it might make a good DIY project -- OWC has the best video available on macsales-com INSTALL VIDEOS: how to upgrade the main drive in a 27 inch iMac 2017 (same procedure as 21.5" 2017-2019 models)

tenorclef31 wrote:

PS- if clicking is an issue that could cause further hardware failures outside the hard drive and it is costly just to get someone to take out the drive I am not going to use is there way of getting the iMac to ignore the fusion drive on booting completely to avoid the clicking even if it is no longer recognised on DiskUtility?

There is little to no potential for the failing drive to affect other hardware in the Mac.

However, it can affect the performance as you note the behavior at startup when the Mac queries the internal drive before it moves on to the SSD.

I agree with @den.thed's posted guidance.

If you're booting and running successfully from the external SSD then you can delete the entire Fusion drive. Then it should not be involved in your boot process and should not make any sounds.

heh, heh -- im w/ u on the unintended sarcasm (my bad writing)

i stopped at 2017 hardware and Mojave (for cs6 photoshop indesign acrobat) -- until 2024 when i discovered 2019 iMacs run Mojave and Sequoia -- that's when I first loaded Sequoia (tho i can't run photoshop since i don't have an Adobe subscription) -- i appreciate the working web browsers

my oldest working machine is 2011 mac mini running Snow Leopard 10.6.8 with a couple driver hacks to make the video work -- i still use it almost daily tho the browsers are generally worthless and it doesn't activate the old software so time is running out on it

2017 iMac (in 2023) was my first time cutting off the screen and flipping the main board to upgrade the fusion NVMe SSD -- done a lot of 2019 iMac SSD upgrades after that to flip -- OWC has the best videos

personally, i would not depend on an imac with a clicking or failing HDD -- 2017 and 2019 imacs running Mojave are still very useful hardware BECAUSE they will still Activate and run cs6 for a few more years -- as long as you activate it before the servers are disabled (any day now)...

Aren't you a little out of breath -g

Some of us still have the old vintage Computers ,with the old OS.

Samsung 970 EVO is not an issue for us, replacing the HDD, with an new SSD HARDDRIVE!

"IF THAT 2017 IS WORTH YOUT TIME".........................come on mr. -g....................................

I am so humble, in these times!

I completely agree on this issue with Old Toad!

I have the same 2017 iMac , but completely without "Clicking Noises", after failure!