Had an 80GB Seagate ST380815AS 7200.10 come in. Diagnosed as a head failure. This is a VERY simple drive, single head. I had 3 parts drives in stock that were a perfect match, and I verified that all 3 were working. Swapped out the heads, and the drive still clicked. There is no platter scoring, so I was a bit perplexed. I put the parts drive back together with the donor heads, and it would come ready, but shortly there after it would start to click. I've tried multiple methods of this attempt, using the donor magnets, using the original drive's magnets, resetting the head, everything I can think of.

I'm thinking there is an issue with head alignment. Even though there is just one head, and it is anchored to the drive casing. The second parts drive, I decided to be a little more methodical. I did nothing more than just open it first, and then I tested to see if it would still come ready after I closed it back up. It did. I then moved on to just removing the upper magnet. I opened the drive, removed the magnet, put the magnet back on, and closed it up. Nothing more than that. The drive would come ready but start clicking shortly after. The exact situation I was having with the other drive, and I hadn't even removed the head.

So has anyone else had any issue with head alignment on these drives? It seems worse than some WD BB drives.

Seagate doesnt need special alignment u are not telling us wich was the first "syntomph" means hdd knocks on first?, wich ATA registers was showing, and wich was the terminal log?,


Regards

Thanks for the reply. I guess what I was getting at is, forget about my customer's drive for now and the symptoms with that. I'm more curious as to why the symptoms might have occured on the parts drives. Why would a drive come ready, and then a few seconds later start to knock. 2 of the parts drives are like that now. One of them I removed the head, and when I put the head back in it knocked after coming ready. The second one I was just going to try and go step-by-step through a process of elimination. I opened the drive, closed it, and it worked fine. Next I opened the drive, removed the upper magnet, put it back on, closed it, and it comes ready but starts knocking a few seconds after coming ready just like the first parts drive.

I've never had a problem like this, and it was a little odd. Why would a single head that was not mishandled in any way, suddenly click after it was removed and then replaced. Why would a drive click that had nothing more than it's top magnet removed and put back on?

It just seemed like a really weird problem. Especially on a drive that is so simple. I mean we regularly swap heads and move platters on drives much much bigger than this without much trouble, so it is a bit perplexing, and Seagates have always been one of the easier drives for us.

Problem may not be heads?

Just some possibilities:

Translation tables
R/W Channel
Cache corruption



As for the drives that WHERE working, are you 100% positive they did not sustain any ESD damage? Did the heads touch at all?

On first should be good did a head test by terminal , before did head exchange u can check if its SA problem or its a MHA problem, or even surface by terminal u got some good info, and diagnostics too

Regards

We utilize every possible ESD preventative measure possible. It's a single head, so there were no heads to come in contact with each other. It's just really weird. Picture opening a perfectly working drive, lifting off the magnet, putting it back on, and then starting it and the drive clicks a few seconds after it becomes ready. That is exactly what happened here.

As far as the customer drive is concerned, Terminal definitely showed bad heads which is why we went forward with the attempt to begin with.

Thanks for all the input and advice. I appreciate it greatly.

Have you seen the head that now clicks on microscope ? Do the read channel work ? Eccentricity of the platter ? Vertical vibration of the platter? And, last but not least... HEAD CONTAMINATION ?

In effect, this is a weird case

You may want to double check for head/platter contamination, maybe your flow bench isn't working properly (assuming you have one)


Seems VERY unlikely, but maybe breaking the seal is causing enough of a disrupt in airflow? Sounds too farfetched but you never know.

[quote="gtd4242 Next I opened the drive, removed the upper magnet, put it back on, closed it, and it comes ready but starts knocking a few seconds after coming ready just like the first parts drive.
[/quote]

Then I would suspect something bad around lifting the magnet and having the field ruin the servo on the platter...
Though I have never had such issue yet...

pepe

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Adatmentés - Data recovery

It seems quite strange that the lifted magnet could ruin the servo.... I vote for head damage/contamination.

Did you clean your donor drive prior to opening it? No matter how clean your cleanroom is, if the drive has been sitting in storage, it gathers dust. Even with best facilities and preventative measures, I've often broken the seal on a drive and found dust which has gathered on the seal.

How are you removing the magnet? Using a pliers or salvation-style magnet remover?

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Data Recovery Ireland