• Hello, Guest! Welcome back, and be sure to check out this post for more info about the recent service interruption and migration.

Iomega Zip 100 Drive Click of Death Repair?


Well-known member
I know from firsthand nearly extensive (unfortunately) experience that Iomega Zip 100 drives tend to eventually succumb to the dreaded "Click of Death."  If you're lucky, if you can call it "lucky," only a Zip disk will be affected.  But, sometimes the drive itself succumbs and becomes unable to read Zip disks and might possibly damage good Zip disks to boot.

Question is, has anyone ever found a way to repair a drive that has succumbed to this?  Searching online, I have not found anything.  I did find instructions for replacing the disk reader, which is helpful from a disassembly point of view, but given that replacement drive readers aren't exactly available unless taken from a donor drive, that's not a practical repair solution in most cases.  (Plus, since the drive reader is the part seemingly most likely to be defective, there isn't an abundance of donor drives either.)

I did find a repair guide for the Zip 250, but whether that is applicable as well to the Zip 100, I don't know.  I might have to dig out one of my deceased Zip 100 drives and take it apart to see.  In the meantime, I'm curious as to whether anyone else has found a fix for the click of death?

I'll post the links I found in case they might be beneficial to anyone:

Iomega Z100S2 Disk Reader Replacement


Zip 250 Drive Repair


Also, another site had a short thread with discussion from people that had tried to repair their drives with varying success.


One noted that changing the power adapter on an external unit was sometimes successful.



Daring Pioneer of the Future
Staff member
General thoughts, not advice per se: 

The solution when this was happening 20+ years ago was to replace them, which, of course was easy to do because they were still being made, and probably made the problem worse because people were getting replacements based on updated cost-reduced designs that had worse problems to begin with.

By recollection (I need to research this at some point, even if that means finding my old posts on the topic) there were different causes for the clicking, some of which could be avoided in some way and some of which meant the drive and all media it had touched after a certain point were dead and would infect other drives.

In general, the clicking is indicative of the drive being unable to sync properly to the media to read its contents, so one of the problems was media or heads that had fallen out of proper alignment. This specific error varied in severity and media that worked fine on one drive might not work in another. The main fix was to copy data off the bad media and maintain or replace the improperly aligned drives.

It wouldn't surprise me if, say, aging/failing power supplies was another cause for clicking, but I don't know how well documented that really is.

I've seen some people claim that the presence/absence of bumpers makes certain problems better/worse (i.e. a drive with a bumper or a better kind of bumper might better be able to prevent, say, media ripping, which means you could hypothetically recover from a future click of death by realizing your disks/media are misaligned, copy the data off them, LLF them with Iomega software on a good drive to refresh the format/alignment, then maintain the offending/failing disk, and perhaps add a bumper to it to prevent things from being problematic.

However, I hate to suggest that because I'd presume that the motors and firmware and everything are expecting to be able to retract a certain distance and altering that a lot could cause other problems for the drive.



Well-known member
Also, for whatever it may be worth, and this is only in my personal experience, I have yet to see an internal Zip drive (one that came preinstalled in a Macintosh) fail.  But, I have only used three such drives.  I have used my 8500 (or 8600?) with an internal Zip drive to image a large number of Zip disks (with many more to go).  Some of those Zip disks have had the click of death.  So far (fortunately), the click of death has not been passed along to the internal Zip drive.  I hope that will remain true for the remainder of the disks I need to image, but I secured a backup Zip drive just in case.

On the flip side, every external Zip drive I have used has eventually succumbed to the click of death--some due to the same "click of death" disk the internal drive couldn't read (but was apparently not affected by).  I don't know how many total, but I think a half dozen or more.  Most SCSI but I think one or two USB.



Daring Pioneer of the Future
Staff member
All OEM internal Zip drives are fairly late in the game, I believe all of them fall after at least the first cost-reduction, I forget whether that was before or after 1998 (i.e. did this get worse after the first or second cost-reduction.) If the beige ones don't, all newworld macs with Apple oEM Zip drives (1999) have the cost-reduced models, if they have the original drive in them.

This might just be a symptom, especially on any pro-oriented towers, of the Zip drives not having been used much in these machines when they were new, because, well, realistically Zip was insufficient for their work, and Jaz/SyJet or the like (big MO drives, CD-R/RW) would have been better, due to increasing filesizes those kinds of machines typically/often worked with.

As a historical sidenote - in my mind, Zip made most contextual sense on the 4/5/6/7000 series and PowerBooks, because those kinds of machines typically dealt with smaller files like office documents, emails, small digital photographs, and the like. On Consumer macs specifically, other than Iomega dumping the Zip drives on speculative sales of the media, which may or may not have panned out, including Zip (as opposed to syquest or jaz or tape or MO or a CD burner) makes sense primarily for cost reasons and for ecosystem reasons. You will have been much more likely to be able to buy Zip disks in your town in 1996 than, say, any of those other formats. However, people buying high end Macs (7000+ and powerbooks, in particular) would have been accustomed to ordering supplies from a catalog reseller or going to a major metro with a lot of tech activity to be able to get specialized supplies.

The decision Apple/(Iomega?) made with the 7000 was probably the right compromise for everything above a 6000 which was to make a purpose-built kit available (mostly for the purpose of backporting to 7500/7200) and not offer it as a prebuilt, mostly for the purpose of leaving slots and bays available for their original purpose, letting well-informed, technical users choose what they need.

So, uh, anyway tl;dr to the extent that Apple's Zip drives aren't appearing faulty, my guess is that it's because they all have very few hours on them.



Well-known member
I have an internal Zip drive in my Sawtooth, but it doesn’t read read disks.  I think it’s the original OEM version.  Not sure what the click of death sounds like, but I’m guessing it must have happened to mine.



I haven't looked lately at prices, but I'd suggest replacing any IDE internal Zip100 with a Zip 250 mechanism. They're more useful overall and have been bullet proof AFAIK.



Well-known member
The only solution for me was to replace the disk reader. 

While i looked online a solution to repair my drives and didn’t found any, I was able to found several units for cheap. 

The SCSI is hard to find, but the parallel one is pretty common and sharing the same disk reader. 

So a swap is the straightforward solution. 



Well-known member
From what Cory said, years and years ago, I had three Zip 100 drives, and when one exhibited this type of behavior, I theorized it was from me leaving the power supply in for years. Sure enough, using a fresh power supply got it working with no issues. I have always theorized that it was a power issue more than anything.



Well-known member
The power supply issue is intriguing.  It may also explain why (at least in my experience) internal drives have been less likely to fail than external drives.  (I am making a guess here that the power distribution within the computer system is more consistent and/or reliable than from an external power adapter.)

Has anyone tested the external power adapters on a multimeter to compare the voltage between different units?  Are the power supplies delivering less power as they age?  Something about this feels familiar; I vaguely recall aging power supplies being an issue for something else vintage Mac related but I can't remember specifically what it is.  Maybe I'm thinking of the Newton OMP and 100 models which experience power issues.

It's something to test anyway.  Sometime, I'll have to dig out my box of deceased Zip drives and test the power adapters.



Daring Pioneer of the Future
Staff member
I'm Interested(TM) and, for what it's worth, although clicking might have been a symptom (because clicking, generally, is a sign that the drive is malfunctioning or can't get a read on the disk) if this works, I'd say that it's probably fair to say that what these drives suffered isn't, strictly speaking, Click Of Death, which is a pretty specific set of things, mostly resulting in data loss and sometimes loss of the physical media and sometimes the infection of other units, depending on which particular subcategory of problem you have.

Adding this thread to my wiki notes thread. A thought there is as part of rounding up what options exist and what the pros/cons of each are, how-to and troubleshooting info for each of them might be relevant.



Well-known member
Probably a good idea would be to come up with a best practices procedure.  I don't know if that would be possible here though.  If you stick a disk in a drive and get the clicking, is the disk at fault or the drive?  If it's the disk, did the disk ruin the drive?  So, what's step two?  Try the disk in a different drive or try a different disk in the same drive?

In instances where power issues are to blame, it would be useful to try to figure out at what power levels the problem arises.  Knowing that, the power supply could be tested beforehand, either before first use of a newly-acquired drive or first use after an extended period of not being used.

The best best practice is to not store anything critical on Zip disks anymore.  And, if you have data you want to save (as is true for me), to get the data off Zip disks as soon as feasibly possible.  And then only use Zip disks for the retro experience, not saving important files.

You will have been much more likely to be able to buy Zip disks in your town in 1996 than, say, any of those other formats. However, people buying high end Macs (7000+ and powerbooks, in particular) would have been accustomed to ordering supplies from a catalog reseller or going to a major metro with a lot of tech activity to be able to get specialized supplies.
Meant to reply to this earlier.  At work (printing) back then, we used floppy disks at the start.  I remember having one or two wooden storage boxes for floppy disks to store customer files.  We switched to SyQuest cartridges relatively early on.  Then, moved from the SyQuest 44 to an 88.  When the Zip drive came out, those were great.  (It was years before I had any problems with Zip disks, which is why I used them so frequently, which is disappointing only in retrospect.)  For about half the price of a SyQuest 88 cartridge, a Zip disk held slightly more files and took up a lot less space.  Designers and others started using Zip disks too.  I know SyQuest came out with larger cartridges later and there was Jaz, but I think they had already fallen behind Zip disks.  And then Apple started including Zip drives with new Macs, so I think that was a pretty big nail in the coffin for the others.

The next viable media, IMO, that came about were rewritable CDs and write-once CDs.  The latter caught on quicker, I think.  The former had compatibility issues in different CD readers.  The write-once CDs were more reliable and also less expensive.  And, if you had a CD burner that could write multiple sessions, it was almost like a rewritable in that you could get multiple uses out of it when dealing with smaller files.

Of course, now twenty plus years later, both Zip disks and CDs have proved disappointing.  Zip disks and/or drives die and CDs fade,  both leading to data loss.

But, anyway, we did buy stuff locally (our local computer stores were well-stocked in those days) as well as through catalogs.  And Zip disks just won out either way.  At least until CDs took over.  And later DVDs.



Well-known member
I have a few SCSI external units (and one of the weird Plus combo parallel/SCSI units) and they all seem to be the cost-reduced death-clicker type. I haven't tried using them because I would prefer not to ruin my disks until I fix them.

Anyway the cost reduction was: they removed a very cheap (maybe 5¢) rubber bumper from the rear of the head assembly support/guide/suspension arm. This may not seem a big deal, and it isn't under normal circumstances because the bumper isn't really required for normal operations. However, when a Zip drive encounters a serious error with a disk, its first corrective action is to reset the mechanism and try again. This reset process involves rapidly unloading the heads from the media, which slams the back of the head assembly into the rear of the case. If the bumper was present, this wouldn't be a problem because the bumper would be cushioning the impact and slightly reducing the travel distance by taking up a little bit of space at the back of that arm. Without the bumper, however, the process is much more violent and thus things can eventually become deformed or misaligned to the point where the drive won't work properly and may begin damaging disks.

The fix is to put a very small bumper on the back of that suspension arm and then all will be well. However this is assuming the drive isn't already having problems; installation of the bumper won't cure an already-damaged drive, only prevent a good one from becoming damaged. Nor will it magically resurrect damaged disks. I haven't actually bothered to try to fix any of mine yet so I can't give too much in the way of specific replacements that work. The OE bumper looks to be a custom cut piece of slightly spongy rubber material but I imagine a small o-ring would be a suitable replacement, one ideally slightly less than 1mm thick. Too thick of a bumper will interfere with proper operations and could damage the drive because the head assembly would be unable to retract completely.

With proper storage and a non-defective Zip drive, Zip disks last about as long as any other magnetic media. They're bootable and well-supported by vintage Mac OS (unlike some MOs and recordable CDs), don't really require any special support programs, are relatively quick, and were once plentiful and inexpensive. The biggest failure rate for Zip disks themselves (other than being eaten by a damaged drive) is caused by poor storage: excessive heat will degrade them quickly, dust will ruin them, and excessive humidity can cause mold to grow on the media and unlike dust this cannot fully be cleaned off because the mold eats into the media.