Malfunctioning gauges in am IH? I must be reading these too late at night, It's daytime now and I'm surprised you weren't swamped with stories of gauge problems. Ok, I read the back digests and found your post - must have read these when I was asleep.
" Should work but no fuel, oil or temp, alt works. Fuel always reads 1/2 tank, full or empty, so I guess its right once in a while <g>. Temp is the same way. No oil action though."
A likely culprit when the gauges don't work or work poorly is the voltage
regulator behind the gauge cluster in the dash. There are wiring diagrams
available for the gauges in the service manuals or at http://www.binderbulletin.org/techlib/electrical/diagrams.htm
but these (web page) are listed for the Scout II and I'm not sure they
would help you. The idea should be similar though. I'm not familiar with
your year or type but the common problem that crops up is that the old
mechanical voltage regulator stops working right and supplies an incorrect
voltage to all of the gauges. It is on the back of the temp/oil gauges.
The way the mechanical regulators work from descriptions I've heard is
that when a voltage is applied (12VDC) it heats a coil around a piece of
bimetallic strip. At a certain voltage the strip bends (unequal expansion
between the two types of metal in the strip) and contact is broken cooling
the strip. As soon as the strip cools enough contact is reestablished and
the heating starts again. This all happens quickly and the contacts "buzz"
as the connection is made/broken rapidly. See how this could wear out?
Cheap, simple way of regulating voltage if rapid variations in the output
aren't a factor. Gauge response is much slower that the oscillations. I
believe the output is around 5V but don't know what current is required.
Anyhow this is probably the culprit. All of my info is based on the Scouts
but I think your vehicle would be the same. My apologies if your setup
is completely different but it's a start and easier to check than replacing
all of the senders.
Here is an interesting use of a solid state voltage regulator to replace
the mechanical one originally used.
http://www.binderbulletin.com/faq/5.htm#12
Matt Palguta 1980 Scout II
--
Age is a very high price to pay for maturity.