[ekema]

I am in the process of rewiring my 68 xr7 with a Ron Francis 24/7 and was wondering about the dash panel. Correct me if I am wrong, but it looks like the temp gauge and the fuel gauge are wired through the little voltage regulator in back of the dash panel. Will that still be needed or can I wire directly to the gauges. I am using the original gauges except the ampmeter has been converted to volt meter and the tach has been upgraded too. Both done by Rocketman.

 

[TheRktmn]

The OEM Temperature, Oil Pressure and Fuel gauges all run on 5 volts, so you will need a CVR to power them. If you wire them to 12 volts you will let all their smoke out and they won't work anymore.

 

[ekema]

Thanks Rktmn. So its looks like the brown (gauges) wire on my new harness runs to the CVR first then to the gauges. How are the gauges grounded?

 

[Bad69cat]

On a stock harness there was a little pigtail with ring term on it - just went to the body/dash frame near the drivers side (thought there was also one on the pass side - but I dont remember for sure)

 

[ekema]

correct me if I am wrong, but it looks like the body of gauges ground to the instrument panel frame, then the instrument panel frame grounds to the body/dash frame? Does that sound right?

 

[ekema]

I just thought of something. Mechanical gauges don`t need a ground. right? Silly me.

 

[TheRktmn]

Mechanical gauges only need ground for illumination. The factory gauges ground through the sending units.

12V to CVR -> pulsing 5V from CVR to gauge -> through gauge to sending unit -> sending unit to ground.

It's a misnomer that a sending unit sends - it actually receives the voltage and regulates the resistance to ground. The amount of resistance dictates the gauge reading.

 

[ekema]

Thanks again Rktmn. You are the Man.. BTW. Good luck with the move. Another BTW.. I just purchased the new solid state CVR from Scott Drake. Anybody tried it out yet?

 

[Bad69cat]

No - let us know how it works out....I gotta think it's much more reliable. Probably not much to making one really. I'd like to crack it open and see what makes it tick!