rbt@frontiernet.net wrote:
> > From: Sam Parthemer <srp@home.com>
>
> > You hit the nail on the head Ian... It's the clutch fan. When cold it
> > sticks a little, as it
> > warms up, the clutch frees and the noise goes away... Everyone else has the
> > same
> > 'problem', which isn't a problem.
> >
>
> Yes it IS a problem. Never had this on any other vehicle I've owned.
Ive worked in and around a auto radiator shop for 26 year now. Most veichles
with temp controlledfan clutches do this when cold. Notice I said Most. Many GM
veichles only have a 3 blade fan
which does not sound nearly as loud as if you have a 5,6,or7blade fan. The
larger the fan, or larger number of blades or steeply pitched blades the more the
noise. Also there are at least 2 different
types of fan clutches. One type is temperature controlled and used by most
manifactures. Another
type is only a kind of fluid clutch which is not temperature controled and works
only on engine rpm.
These are typically cheap replacements sold by auto supply stores and not often
used as factory
equipment. The way you can usually tell which type you have is to look on the
front (side towards
the radiator) of the clutch. The thermost controlled fans usually have a flat
coiled bi-metal spring
exposed on the front. The non thermostatic types usually have a smoth metal
plate on the front.
Some day ALL veichles will have electric radiator fans which are controlled by
the computer. These save space, weight, Horsepower, and cool better at slow
speeds or when stopped in traffic. They may not last as long though, and they
cant move as much air as a large, multi-blade fan at higher engine rpms.
>
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 12:08:13 EDT