At 12:04 AM 5/27/2004 +0100, Antony wrote:
>
>I'd be interested to know a bit more about why you think it could be
>voltage regulation - I know nada about the inner workings of the
>alternator.
>
Antony,
It's probably not the alternator. Most of those electric gauges run at
10V. The battery outputs 12V and when the eng is running at about 1000
rpm and above the alternator ups that to about 14.7 V. So the voltage
is 14.7 - 10 = 4.7 V too high, or almost 50% too high. This will cause
an invalid reading on the temp gauge. There should be a little metal
box looking think on the back of the speedo or tach. That's the "voltage
stabilizer" or regulator. If that's shot, or the previous owner removed
it, you'll get too much voltage to the sending unit, and the temp gauge
will read too high.
Another thing you can do, is to pull the gauge, stablizer/regulator and
gauge out of the car. Then get a 12V lantern battery and clip lead the
hole thing together in the kitchen. Now boil some water and stick the
sending unit into the water and see where it reads. That will be 100d C
or 212d F. You can put a small drop of nail polish on the glass at that
needle setting. So you now have at least 1 calibrated point on the gauge.
John
John T. Blair WA4OHZ email: jblair1948@cox.net
Va. Beach, Va (eBay id: zebra48-1)
Phone: (757) 495-8229
48 TR1800 48 #4 Midget 65 Morgan 4/4 Series V (B1109)
75 Bricklin SV1 (#0887) 77 Spitfire 71 Saab Sonett III
65 Rambler Classic
Morgan: www.team.net/www/morgan
Bricklin: www.bricklin.org
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