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1966 coupe and 1970 sportsroof
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Discussion Starter · #1 ·
Midlife sold me a instrument voltage regulator (thanks Midlife!) which got my gauges working again. Problem now is they all register slightly to high... Gas, oil and temp are all a quarter the gauge to high... The voltmeter also sit's a little high but twitches when the turn signal is on!

I was about to buy a voltage regulator but wanted to check with you guys first...

Any thoughts?
 

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The instrument regulators have an adjustment screw on them, which I believe has a tamper resistant coating on it. Don't know which way you need to turn it, but you could give that a try. It'll vary the effective voltage used by your gauges. As for the voltmeter, that sounds normal to me.
 

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Woodywrkng nailed it.

Lance: look at the back of the CVR, and you'll see some red goop covering a small little post. Break the red goop, and with a tweezer, grip the post and rotate it 1/2 turn (doesn't matter which direction), then remeasure your gas tank reading. If it reads higher, then you went the other way. If lower, continue in that direction until your tank reads correct. I use 1/4 tank as a good calibration point.

BTW, my car also read high with that CVR, so you're on the right track.
 

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1966 coupe and 1970 sportsroof
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Discussion Starter · #4 ·
Ah-ha! Thanks guys! BTW, who is Lance? /forums/images/icons/smile.gif

So why does my voltmeter twitch up and down with the turn signal on... It never did that before...
 

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Hey Mid,

My gas gauge reads low, even though I just replaced the sending unit. Can I turn an adjustment screw somewhere to increase voltage, or do I need a new instrument voltage regulator too?

Phil
 

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Could you use a 5v solid state regulator instead of the CVR? (From my experimentation the CVR oscillates somewhere between 0-12v, so I figure around 6v if it is 50% duty cycle)
I think my CVR may be a little unhealthy and thus the low temp fuel and oil readings on my guages (Ive measured the oil @ 40-50 psi with a mechanical guage, but it sits right at the very bottom of the oil pressure guage.)
 

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Ooops! Sorry Lance...I mean Shaun. Dang, I can't tell you two apart. I guess I'm gonna have to come out there and meet you face to face, so I will be able to.

I'm getting more and more senile....CRS!
 

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Yes you can! But you will also adjust the same amount for gas, oil, and water temperature. You sure you want your engine to "overheat"???
 

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1966 coupe and 1970 sportsroof
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Discussion Starter · #10 ·
It's easy, I'm the good looking one!

Why don't you come out this weekend and we'll test your stomach with a few laps of Sears Point?! /forums/images/icons/smile.gif
 

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Yes, you can use a solid state voltage regulator. But get one that you can adjust. Even if you got a perfect 5.00V regulator, the gauge still may not read correctly. I always adjust mine to the gas tank, as that is the most critical reading of them all. Once that is done, I note "normal" readings of oil and water temp, and then just look for anomalies from their normal settings.

I believe the CVR's are spec'ed to 6V, but the Shop Manuals don't give that number out.
 

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Randy:
You have to make a "substantial deposit" in BofM to examine my teller in the flesh: face and all. Bank hours are from 11AM to 2PM, with Lunch from 11:30 - 1:30. MWF only.
 

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Make sure all of your grounds are good.
Mine read very low until I found I had a bad ground from the tank to the body.
I hot wired a new ground and my reading improved alot.

John
 
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