Path: utzoo!utgpu!utstat!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!rutgers!ucsd!sdcsvax!ucsdhub!hp-sdd!hplabs!hpfcdc!hpislx!hplvli!boyne
From: boyne@hplvli.HP.COM (Art Boyne)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Cheap fix for ST4051 hard disk problem
Message-ID: <360011@hplvli.HP.COM>
Date: 19 Apr 89 18:19:25 GMT
References: <8059@boulder.Colorado.EDU>
Organization: Loveland Inst. Div
Lines: 21

caf@omen.UUCP (Chuck Forsberg WA7KGX) writes:
>In article <8059@boulder.Colorado.EDU> lilley@boulder.Colorado.EDU (John Lilley) writes:
>I have a 4051 that won't start up unless it is 1) warm or 2) is jiggled
>about its rotational axiz to help it get going.  Once it's spinning
>all is well, but a few hours of power-down and it won't start.  Is
>this the tesult of a weak motor controller chip or bad lubrication?

Neither: the ST4051 had a production problem a couple of years ago with the
spindle motor seals.  With time, the spindle motor would outgas a sticky
material onto the inner tracks of the media - guess where the heads park
at power-off!!  Enough material eventually collects on the media to cause
the heads to stick to the platters, preventing spin-up.  You can usually
break the "stick-tion" by manually turning the spindle motor, or as suggested
above, twisting the drive in its rotational plane.  However, you run the
risk of eventually ripping the heads off the actuator.  The only long-term
solution is to replace the drive.

BTW, I have one of these eventually-to-go-bad drives.  Bought it at a company
scrap sale for $80.  I try to keep good backups!

Art Boyne, boyne@hplvla.hp.com