Instrument Voltage Regulator

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jhdeval

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I read an article over at earlycuda http://earlycuda.org/tech/gauge-convert.htm and it intrigued me. So here is my question. My voltage regulator is blown why not, rather then make the regulator an add-on, wire it directly into where the mechanical regulator is? Does any one have a picture and or information as to how it is wired? I have some electronics experience and from what I can tell the only place it is used it to power the gas gauge and the temp gauge. If that is the case there should be no issue with wiring it directly. It would give a constant 5 volts out. Would that cause any issues? Did the mechanical voltage out fluctuate and if so was there a purpose for the fluctuation?
 
You'll need to find out if your limiter is a plug in can type or housed inside the fuel gauge.
Some instrument restoration companies now use my DeMonIVR solid state regulator rather than rig up something. I guess they want 100% happy customers too.
 
Just like that. Thank you very much. Any thoughts on why my speedo isn't working? I understand the premise behind how it is supposed to work but I can't find any way to test that the speedo cable is doing its job.
 
Just like that. Thank you very much. Any thoughts on why my speedo isn't working? I understand the premise behind how it is supposed to work but I can't find any way to test that the speedo cable is doing its job.

Well it can be frustrating, there are several possibilities:

the cable is broken inside the housing

the gear (which is plastic) is damaged, either the gear teeth or the square socket which mates with the cable

the gear is installed wrong--notice the plug which holds the gear in the transmission has index marks--it is "eccentric" so rotating the plug allows bigger or smaller gears to be installed

Or the trouble may be right in the speedo--some sort of internal damage to the instrument.

Probably the best way is to put a "small load" on the cable to be sure the gear is not "stripping" or that the square cable drive at the transmission gear is not slipping. You can disconnect the dash end, either drive the car a short distance, or run the car in gear with the (carefully) front wheels blocked and rears jacked up, then feel the cable end with your fingers, and squeeze gently with your fingers or a rag to see if it still turns.

If you replace the cable, you can buy a "universal kit" that replaces just the drive cable itself, not the outer jacket. Be careful with this, because if the jacket is old, or has poor lubrication, or has been damaged by the failed cable, the jacket will be rough inside, and will quickly wear out the new drive cable.
 
For the voltage regulator, I purchased the one from Real-Time Engineering. It was easy to install and works great. Here is picture of it installed...
 

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For the voltage regulator, I purchased the one from Real-Time Engineering. It was easy to install and works great. Here is picture of it installed...
Don't you need to modify the fuel gauge to eliminate the original voltage limiter circuit?
 
Don't you need to modify the fuel gauge to eliminate the original voltage limiter circuit?

Only on those panels that have the limiter in the fuel gauge which is a smaller percentage of them.
 
For the voltage regulator, I purchased the one from Real-Time Engineering. It was easy to install and works great. Here is picture of it installed...

If ya have not re-installed that dash, yet, it'd be a good idea to replace the radio suppression capacitor (condenser) If it shorts, bad things

Should be available from any "real" parts store, ask for a "radio suppression capacitor" or look through the pictorial guide for just about anything with similar mount. You might have to cut and splice the wire
 
solid state regulators don't make the pop noise so the suppressor is not required.
 
solid state regulators don't make the pop noise so the suppressor is not required.

Geez I don't know where my brain went there......

but you should remove it, you certainly don't want that 40 year old cap to short...........
 
Don't you need to modify the fuel gauge to eliminate the original voltage limiter circuit?

Yes, I had to modify the fuel gauge to disable the old voltage limiter.

If ya have not re-installed that dash, yet, it'd be a good idea to replace the radio suppression capacitor (condenser) If it shorts, bad things

Should be available from any "real" parts store, ask for a "radio suppression capacitor" or look through the pictorial guide for just about anything with similar mount. You might have to cut and splice the wire

Is this a common problem? I have not heard of the issue. I can easily reach up there and disconnect it.
 
Geez I don't know where my brain went there......

but you should remove it, you certainly don't want that 40 year old cap to short...........
Has anyone ever had this happen? I've found some with the wire broken off but never one that shorted/grounded. I think I've only sold 3-4 of those in 30 years and they were all for ones that were missing, not bad.
 
I'm sure it has happened. I haven't seen it first hand. I have seen a condenser short to ground and disable point type ignition..
The nost common fault with the noise suppressor is connecting it wrong .
Factory placed a plastic cap similar to a wire nut on one of the fuel gauge posts in a rallye panel to block attaching the suppressor there.
 
66cud-s

A coupe of things:
1. Can I get a parts list from ya?
2. Is that a capacitor stting off to the side?

Bear
 
66cud-s

A coupe of things:
1. Can I get a parts list from ya?
2. Is that a capacitor stting off to the side?

Bear
Some of the above links have the part numbers. The metal "can" sitting off to the side by the speedo, is radio the noise suppressor we're talking about.
 
66cud-s

A coupe of things:
1. Can I get a parts list from ya?
2. Is that a capacitor stting off to the side?

Bear

Hello. Yes, go to rt-eng.com to get the voltage limiter. Then all you need is some wire and crimp on connectors. Real time engineering provides a good instruction sheet that shows you how to disable the stock voltage limiter and install the new one. I have more pictures if you want me to post them. Enjoy.
 
I have to say that I am verify happy I asked the question. First time I sparked a good thread. Thank you to all that have contributed I greatly appreciate it.
 
To narrow down the speedo issue. Get a friend to sit in the car. Remove the plug the cable is connected to at the trans. it has index markings on it. Spin the gear by hand, like snaping fingers. Ask the person is the speedo moved. If not spin the other way just to make sure you spun it the correct way. It the speedo jums a little the problem is not the gauge or cable. Maybe the plastic gear or trans. just a thought
 
Thank you HemiPar that is a really easy way to test it. Also your Dodge Caravan have you not seen the new commercials for the Honda Mini Van I think. You could make it ROCK lol sorry they really have tried to make the mini van sexy I just dont see it.
 
I don't see sexy in them either. Wife wanted to get new vehicle this year, till we found out I get laid off on Jan 3. So now we have to put money in it to keep it going till new job can be found.
 
I have a 66 Barracuda. Is the instrument regulator inside the gas gauge or on the back of the panel.
Thanks
 
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