John,
If your car is fitted with one of those "Viscous Coupling" fan
assemblies, this might be the source of your noise. From what you say,
it appears that it may be related to the fan since it appears only to be
a problem before the car warms up.
I'd be interested in knowing what you find.
Regards,
Joe
Jjcousins@ra.rockwell.com wrote:
>
> Can anyone offer any ideas on this, please?
>
> Background: I have rebuilt my 1977 Spitfire in the last 3 years. I didn't do
> ANYTHING to the engine as it ran well when the car was in shambles, so I just
> went with it. I drove it all last year for ~1000 miles.
>
> First Clue of problem: All last year (and now) when car was warm, i.e. been
>on
> highway or 45mph for a while, when shutting engine off and engine was cycling
> slowly to off, it sounded like, for the last few turns of the engine, a really
> RRR. RRR, RRR sound with each turn of the engine. Sort of sounded like your
> teeth grinding, but more metallic of course. I put up with it and it still
>does
> it.
>
> LATE last year, and now. When cold, at certain LOW RPMs (like 1000-1500) a
> rattle sound almost EXACTLY the same noise as the above described noise
>happens.
> It will go away when RPMs are increased. But comes back at the same range of
> low RPMs. The noise, also would cycle - last for 1/2 second, then off for
>maybe
> 3 seconds - then repeat. (Was not directly related to engine turns). When
>car
> gets warm, this seems to go away (that is, after driving down a long street,
>and
> then stopping, it didn't seem to do it anymore). Then, when the car shuts
>down,
> I get the noise on the shutdown like above.
>
> It really sounds like metal not having lubrication somewhere and sounds like
>its
> coming directly from the engine. Could there be some lubricant needed
>somewhere
> - not just oil in the engine? I just changed the oil before my first drive a
> couple of days ago. It didn't have any effect. How about the mating between
> two surfaces somewhere? Flywheel? I don't know anything much about inside
>the
> engine/tranny (obviously).
>
> I have NO clutch or shifting problems at all. I know the car is running too
> rich and need to fix this ( I think - judging by the smell of the car). Did I
> damage something by running too rich all last year?
>
> HELP??
>
> John (1977 Spit)
--
"If you can't excel with talent, triumph with effort."
-- Dave Weinbaum in National Enquirer
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