Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site alice.UUCP
Path: utzoo!linus!decvax!harpo!eagle!alice!wookie
From: wookie@alice.UUCP
Newsgroups: net.auto
Subject: Re: speedo blues
Message-ID: <2131@alice.UUCP>
Date: Mon, 22-Aug-83 16:19:01 EDT
Article-I.D.: alice.2131
Posted: Mon Aug 22 16:19:01 1983
Date-Received: Tue, 23-Aug-83 08:51:09 EDT
References: <1476@tekid.UUCP>
Organization: Bell Labs, Murray Hill
Lines: 28

Speedometers are typically driven off the output shaft of the
transmission (some are taken from one of the wheels).  The only
thing that will affect thaese the transmission takeoff type is tire
size, rear axle ratio, or the speedometer driceve gear.  Since
the tires do not account for the cghange and I assume you haven't
changed the rear axle to a different ratio then maybe the
gears in the transmission are wrong.  Have you had the transmission
changed lately?  These gears are usulyyally easily chengesd without
removing the transmission from the car.

However, assuming that none of these things have occurred, then
the speedometer itself must be going bad.  The thing works by
having the speedometer drive either a fluid or friction clutch
in the gauge itself.  If the clutch should increase in friction
for some reason then the raeading will increase.  I have seen
them wear out the other way where the reading drops.

a Tesa testA test for this would be to compare the speedometer with the odometer.  
If the clutch is at fault then the odometer should
still read accurately so find a source of known mileage
and see if the odometer agrees.  If it too reads high
then I think you had better take another look at the
tires, rear axle ratio and transmission speedo gears.

Let us know.......things like this are intrigueingfascinating

				Keith Bauer
				White Tiger Racing