Sounds useful. Why don't you put the schematic and instructions up in the
web?

wrote in message
...
I put this up 3 months ago and it was assumed I was trying to market a
product. Not true I am way to lazy for that. I would rather go
boating.
I did make one and I am very happy with the results.
I have the regular Teleflex gauge set (water temp, oil pressure, fuel
and volts)
They use resistive sending units so the reading is proportional to the
divided voltage. Using a 30 cent comparator and a pot I can pick off
the voltage/reading that I am concerned about. I have them set
somewhere between "normal" and the engine beeper. An anomaly sounds a
beeper (different than the engine) and the bipolar LED under the gauge
goes from green to red. The one that really has saved me several times
is the temperature. It warns me that I am having a cooling problem
long before the engine complains so I can have time to make a safe
stop and get the grass/bag or whatever off. If you are out in a busy
channel that is a handy thing. I would a lot rather know about this at
150 degrees than 200 when the engine beeper goes off.
If anyone wants to make one, send me an email and I will tell you what
I did.