Quick steps to service a broken floppy drive

The floppy drive's low cost and ease of installation have made it virtually disposable. But what if you just can't bear to replace a drive until you're sure it can't be fixed? This article tells what parts you can and can't service within a floppy drive.

In previous articles, I’ve explained how to determine whether a floppy drive problem is related to the floppy drive itself, the disk controller, or the disk. I’ve also walked you through the process of doing some minor troubleshooting, such as checking loose cables, etc. By following the steps in those articles, you should be able to identify where the problem lies. And, if you’ve determined that your floppy drive has problems, but those problems aren’t related to the cables, controller, or disk, there are some steps you can take to attempt to repair the drive. In this article, I’ll walk you through some common floppy drive service and repair methods.

More floppy drive resources
If you've missed any of Brien Posey's previous articles on troubleshooting floppy drives, you can catch them here along with other related TechRepublic articles and columns:

Before you begin
Before I explain the actual repair techniques, I must emphasize that there are problems you won’t be able to repair. Even though floppy drives cost less than 20 dollars these days, they're still complex pieces of equipment. Floppy drives rely on computer-controlled motors to move the disk and drive heads into the correct position to read or write data. There’s really nothing that can be done from a user’s perspective to repair a dead motor or an electrical problem with the floppy drive’s circuit board. If you have this type of problem, it's game over: Go buy a new drive.

Motor problems
It’s easy to tell when you have a motor problem. If you don’t hear the disk spinning when you attempt to access the drive, but the drive’s light comes on, you can be relatively sure you have a motor problem. The light proves that the drive is getting power, but the drive motor that spins the disk, shown in Figure A, isn't working.

Figure A
The drive motor connects to the metal center of a floppy disk and spins it at either 300 or 360 revolutions per minute.

A second stepper motor moves the read/write heads (Figure B). If you attempt to read or write a disk and you can hear the disk spinning but can’t hear the heads moving, you probably have a stepper motor problem.

Figure B
The read/write head assembly in this floppy drive is connected to the stepper motor via a screw drive shaft.

If you have either of these symptoms and an older drive, it is possible that a belt that connects a motor to the physical hardware could have broken or come off the track. It’s pretty much impossible to get a replacement belt, although I did once see someone use a rubber band as a spare belt to get them through the night until the computer store opened the next day and they could get a new drive. If a belt has simply come loose, it’s usually easy to slip it back over the disk spindle wheel and the wheel connected to the drive motor.

Read/write head problems
Fortunately, motor problems and electrical problems are rare with floppy drives. The vast majority of physical problems with floppy drives have to do with the read/write heads. This is good news, because these are the only serviceable components in the drive.

Most of the time when a read/write head has problems, it’s either dirty or out of alignment. To find out which is the case, try to perform a complete format—not a quick format—on a disk. If the format is successful, write some data to the disk and then remove and reinsert the disk and try to read the disk. If you are able to read the data on that machine but not on any other machine, the drive heads are out of alignment.

In the past when floppy drives cost hundreds of dollars, it would be time to get out the oscilloscope and align the heads. However, with floppy drives being so cheap, head alignments are a lost art. It’s cheaper and easier to replace the drive than to align the heads.

If you suspect that the heads are just dirty, you can try using a can of spray air to remove any dust from the drive. Floppy drives tend to accumulate an amazing amount of dust.

If after removing the dust, the drive still doesn’t want to read or write, I recommend unplugging the computer and removing the floppy drive. Next, use a cotton swab with alcohol to clean the drive heads. Alcohol is a solvent and will remove any stubborn dust, oxidation, etc. from the drive heads. Just make sure to let the heads dry completely before plugging the drive back in.

It’s often cheaper to replace a floppy drive than to repair it. However, if the problems are related to a loose belt or dirty heads, you can quickly and easily fix the problem yourself. In my next article, I’ll show you what to do if the problem turns out to be a disk rather than the drive.

Join the floppy drive debate
TechRepublic members have been sounding off on their opinions of the venerated floppy drive. Some believe it's time to put this nearly 20-year-old technology out to pasture, while others can't imagine a PC without their 3.5-inch friend. Join the discussion and tell us what you think.


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