This is pure speculation.... It sounds like something is spinning on
after the engine stops turning for a couple of seconds. It also sounds like
it's something that isn't supposed to turn. Do you had a water pump pulley
with dual grooves to drive the air pump and no air pump? Somewhere I heard
that some of these were stamped pieces that were pressed/riveted together.
It could be that the unused pulley is spinning on the shaft after it heats
up and expands a little.
Just another SWAG.
From: Phil Vanner <email@example.com>
To: 'Edwin Vaughan' <firstname.lastname@example.org>; 'MG NUTS'
Date: Wednesday, April 21, 1999 4:26 PM
Subject: RE: Noise from engine compartment
>The alternator fan fouling the alt body? Is there a bearing in there that's
>dying and as it lets go the belt tension is pulling the fan/pulley out of
>alignment? The fan (I'm talkin' engine fan now) may be fouling the shroud a
>bit, but I would expect that to make a godawful noise audible at all times.
>Good description of the sound, BTW.
>From: Edwin Vaughan [SMTP:email@example.com]
>Sent: Wednesday, April 21, 1999 2:17 PM
>To: 'MG NUTS'
>Subject: Noise from engine compartment
>Yesterday afternoon I pulled into my drive way, shut off my '77 MGB and
>noticed a sound like a table saw makes when the power is shut off (kind of
>a slinnngggg chang chang chang). I thought something might be fouling one
>of the pulleys. I popped the hood and found nothing. I started the car up
>and shut it off again....no sound. This morning after driving the car 10
>minutes, maybe, I shut it off and the sound was there, just muted. Again
>this afternoon, after driving for about 10 min., I shut the car off, it
>ran-on or dieseled for a couple seconds and the sound was more chunky. The
>alternator is not loose and the fan pulley is not loose. What could this
>"I try to think but nuthin' happens"| The MG Filling Station
> -- Curly (the stooge) | http://www.auburn.edu/~vaughme