6 Volt to 12 volt --gauge problems

[jsmithtss]

  I've just changed my 47 Cad. from 6 volt to 12 volt.  The old 346 flathead starts like a champ and runs fine, but my temperature gauge goes to " hot "  after warm-up.  I have tried putting a resistor ahead of the gauge ( + ) and after it. Neither have worked.  I've also installed a new thermostat with the same result.  Can anyone suggest what else I could do to solve the overheating gauge?  Could I put in a 12 volt temp. sensor and cure the problem?
  Thanks

[Coupe Deville]

I would think putting in a 12 volt tempature gauge would solve the problem but you might have to get a new tempature switch. In not sure Good Luck

[bcroe]

I've just changed my 47 Cad. from 6 volt to 12 volt.  The old 346 flathead starts like a champ and runs fine, but my temperature gauge goes to " hot "  after warm-up.  I have tried putting a resistor ahead of the gauge ( + ) and after it. Neither have worked.  I've also installed a new thermostat with the same result.  Can anyone suggest what else I could do to solve the overheating gauge?  Could I put in a 12 volt temp. sensor and cure the problem?   

I think the straight forward solution, is use a small electronic regulator to drop the temp gauge circuit supply from 12V to 6V.  Otherwise you are redesigning the circuit to accomplish the equivalent.  Bruce Roe

[pauldridge]

You do need to drop the voltage to 6V for all the gauges.  Ford used an instrument voltage 'regulator' in their 1950's pre-12V cars, you can get one of those from NAPA or other stores for $20-30 dollars.  Don't just try to put a resistor inline... these gauges need a consistent voltage to function properly.

Here's a link to one at Napa:

http://www.napaonline.com/Catalog/CatalogItemDetail.aspx/Instrument-Cluster-Voltage-Regulator/_/R-ECHIR1_0344444980

And, of course, with the proper voltage, your original 6V sending unit should work just fine.

[jsmithtss]

  THANKS GUYS!!!!!  I have ordered a voltage reg. and will install some time next week.
    Phil, thanks for the link to NAPA, it really helped. ( Love your Pic.)  I was surprised and very pleased with all of the quick responses .  Thank you so much.
                                          J.Smith