Ah, forgot to mention that HDD led is constaly flashing....

Old drives from this era are notorious for a phenomenon commonly known as "stiction", where the read-write heads will become physically stuck to the platters due to a protective coating on the platters degrading with age. The most common way to free a drive suffering from stiction is to give it a swift "twist" to try to free the platters. This can usually break the heads free and allow the drive to be powered up.

However, be aware that (as far as I am aware) there is no permanent fix for stiction, and if you leave the drive sitting unused for extended periods, it will likely get stuck again. How long it has to sit before getting stuck will vary depending on how far the stiction has evolved (could be weeks, could be a few days, could even be as little as a few hours). So, if you plan on using this drive with extended periods of downtime between uses, you may have to twist it every time to get it to start.

Also, a warning...DO NOT TRY TO FREE THE HEADS BY MANUALLY MOVING THE HEAD ACTUATOR, THIS CAN DAMAGE THE DRIVE!

Yes... stiction was common with many MFM and early IDE drives.

I'd add only one thing:
Often it is *only* possible to overcome this by giving the drive a "twist" in *just the moment when it spins up*.
Also you may need to find the optimum direction, cw or ccw.
Some drives (usually ST-40xx) needed a real hard twist, had to be "slapped" in the moment of motor start up.

Hi, good news the twist trick actually worked and now the disk is working normally.

It came ith a DR DOS 6.0 from Digital research installation, a windows 3.0, and some other misc software, thanks for the input!!

Yeah that trick also works with Conner hard drives as well, if they didn't had the sealing rubber turning to goo, they of course stuck.

Also early WD Caviar models also suffered from the same stiction issue, a good ol' whack and they ran back again.

Funny, I am currently trying to get a 8425F running. Its spinning up, but at the beginning the heads were not moving at all.
And yes, I manually moved the head actuator. Now its starting moving the heads at the self test, but it get stuck and does not finish. Dont think there is much to save here.

Error codes are described here
https://stason.org/TULARC/pc/hard-drives-hdd/ … -MFM-ST506.html
But I didn try to decode it so far as the error is obvious...

Well if i power off the HDD in a few minutes goes back to the "stiction state" so there is no a "permanent" fix for this...

Another possibility that can cause an old drive to not spin up under its own power is thickening of the lubricant in the bearings due to age. Twisting the drive to get it running, then letting it run for an extended period can help remedy this to some degree. But, just like with head stiction, letting it sit for extended periods between uses can cause it to get stuck again. It's even worse when there are rubber seals or gaskets that have degraded, which as Vynix already said is common on old Conner drives, but possibly other brands or models too depending on how they were manufactured. Unfortunately, if the problem is due to goo-ified rubber seals, then running it for extended periods may not help.

If it's a bad seal or thickened lubricant, it MIGHT be possible to disassemble the drive and repair it, but you'd have to ask someone much more knowledgeable than me about the process. I have seen video of someone disassembling a drive to replace a goo-ified rubber ring on a drive head parking retention pin, but not yet the actual spindle or motor (not saying it isn't possible or has never been done, I've personally just never seen it).

Using seewer machine lubricant in the stepper mottor has improved the number of times it power on normal, its a nice trick.