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| | | | Joined: Oct 2009 Posts: 46 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2009 Posts: 46 | I have a dilemma, how can you tell if the new gauges, gas, oil pressure and temp are 12 volt or 6 volt. It is a 80 MPH speedo and 100-220 temp and 0-30 oil pressure. I have a full pressure 1956 235ci engine. I will be changing all the wiring to 12 volt with Alternator One wire. Do I need the DA plug? Do I need to change the gas sending unit or any other gauges.Is there a test I can perform to test to see if they are 6 or 12 volts units,,,,,Help
Thanks in advance, Gerry | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | assuming the gauges are original type, oil, temp, and speedo are all mechanical on a 53, so no volts involved, a 53 gas gauge should have a dropping resistor added .... a 30# oil gauge will likely get pegged by a good 235 when cold ... the DA plug will be needed
Bill | | | | | Joined: Oct 2009 Posts: 46 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2009 Posts: 46 | Well why can you buy 12 or 6 volt gauges?
Speedo is cable
Pressure is a copper tube
But gas gauge and temp gauges in volts, Rights? and is the gauge have to be changed or sending units or both, I`m confussed
Help | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | anything is possible aftermarket, did you buy new gauges?
if the tamp gauge is electrical, than it should be fine on 12V, but the original would have been mechanical, although some folks mistake the small tube for a wire, especially if it's been cut when removing the gauge .... nothing has to be changed, the electrical senders provide a resistance, but for a 6V gauge to read correctly with higher voltage a "runtz resistor" needs to be added inline, they're available at most of the vendors
Bill | | | | | Joined: Aug 2012 Posts: 566 Shop Shark | | Shop Shark Joined: Aug 2012 Posts: 566 | maybe another easy way to tell is check the instrument bulbs to see if they are stamped with what voltage. Just a thought
"As I lay rubber down the street, I pray for traction I can keep, but if I spin and begin to slide, please dear God protect my sweet ride." -Amen 56 Chevy 3100 | | | | | Joined: Oct 2009 Posts: 46 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2009 Posts: 46 | I had bought some reconditioned instruments but after buying them I forgot to ask if they were 12 or 6 volt. No bulbs in them. Is there a test I could do to determine what voltage they are? Mostly the fuel gas gauge if worried about because they come in both voltages
Last edited by trihawker; 12/09/2013 4:59 AM.
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | The dropping resistor mentioned would be 30 ohms, 2 watts. If you hook up the resistor, gauge and a tank sender, you can test it out on the bench on 6 volts. | | |
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