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Gauge Accuracy

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Bugeye58

Yoda
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How many of you have actually checked the accuracy of your gauges? Simply, a known good direct reading oil pressure gauge hooked up and compared to the reading in the dash, or something as simple as a candy thermometer in the radiator to see what the temp really is?
Just curious.
Jeff
 
I test thermostats before I put them in with the candy thermometer. They can arrive DOA. Temp guages only when there is a problem (go to a radiator shop and have them shoot it with the gun, and it reads different at different pl;aces). The speedo by clock on the freeway between mile markers then do the math.
 
Gauge accuracy is worth some attention. My GT6 had a Smiths oil gauge (added by a PO) and a Smiths water temp gauge. I had noted that my oil pressure was abnormally low, especially at idle about 10-15 lbs. The temp was always very low, too, but with the C-N-H indicator, I never knew the temp.

I recently installed a dual Smiths oil pres/water temp gauge. I tested the gauge's water temp with two candy thermometers (perfect) and checked the oil pressure with a friend's external gauge. The external oil gauge showed about 30 lbs/in at idle.

The old instruments were wrong. Now, my new guages shows idle oil pressure at about 30-35 lbs. and the temp stays around 165 in this cool weather.

At the least, I'd recommend testing the water temp gauge in a pot of water with a candy thermometer. It may save your (engine's) bacon.

I also strongly recommend that you perform this candy thermometer test when your wife or S.O. isn't looking.
 
Well, when I got the car my tach was way off, so I calibrated it against a tach/dwell meter I have. Does that count?
Then there's math I did to check if my speedometer was right and I thought it was close enough.
Everything else seems 'normal' so I haven't bothered.
hammer.gif
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr> I also strongly recommend that you perform this candy thermometer test when your wife or S.O. isn't looking. <hr></blockquote>
Mark
Yeah. What is it about using an instrument that then gets cleaned that is so upsetting?
smile.gif
 
I hate to say this, but I truly believe it's a "girl" thing. Incomprehensible to male LBC enthusiasts, obviously.

Oh well, now I have my very own candy thermometer which I purchased to preserve domestic tranquility.
 
Iggy, you posted that you calibrated your tach against a tach/dwell meter. How did you calibrate your tach? Is it a Smiths tach?

My Smiths tach seems to be about 200 rpm off from my dwell/tach meter. I'd love to get it right.

How is is done?
 
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