David Brodbeck wrote:

>On my '75, I had a home-made digital temp gauge.  I used an LM34
>"Precision Fahrenheit Temperature Sender", which costs a few bucks.  The
>great thing about this sender is that its output voltage is simply the
>temperature in degrees F times 0.01V.  It's accurate to +/- 0.5 degree.
>  For a readout I used a digital LCD panel voltmeter, with the decimal
>point wired to be two places to the right of where it normally would be --
>this gave a direct readout in degrees F.  The sender comes in several
>formats; I used the version that's in a TO-92 transistor case.  This was
>an aircooled engine, so I glued the sender between the fins at the bottom
>of the oil sump.  It worked pretty well.

LM34 is a great part!  I've used the little devils before.
Add a dirt cheap digital voltmeter. (Harbor Freight often has
them for under $5) and you've got a nice digital tempertaure
gauge...
The LM34 is good from -50F to +300F, which is plenty for a cooling system.
The TO-92 case is plastic. The TO-46 metal can might be better
for adapting to cooling system.... maybe.

For anyone interested, here's the data sheet for them:

http://instruct1.cit.cornell.edu/courses/ee476/labs/s2003/LM34.PDF

Steve
'86 Westy