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temp gauge

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10V power supply. "FULL" at 10V. Dunno what the sender's resistance is at "EMPTY". A Radio Shack potentiometer of proper resistance at "full choke" would give you a good test setup. BCF'r Doug "DKLawson" has a GREAT tretise on just this subject. I keep forgetting to "mark" it but a search should turn it up.
 
So, the best operating temperature is half full? /bcforum/images/%%GRAEMLIN_URL%%/grin.gif

R.
 
Okay, smartarse... "H" and "C" ... The gauges are essentially the same. /bcforum/images/%%GRAEMLIN_URL%%/smirk.gif


boy do I miss those emoticons...
 
Hehehe...

Actually, this is good and timely info. (A bit of a "Doh!" moment also, 'cause it's totally common sense.) I just get a new/old fuel gauge to replace my old one and since the car is down right now (carbs're out) I wanted to test it - without crawling underneath to unhook the power to the fuel pump.

R.
 
Most times with ~fuel~ gauge problems (notice I've now made a distinction /bcforum/images/%%GRAEMLIN_URL%%/smirk.gif ) it ends up being a sender problem. Same with the later (electrical) temp gauges. You can ohm out both of the "business end" devices easily. A thermometer and a pan of water on a burner for the temp, unfortunately the tank sender requires removal to check. Bit more hassle but it'll confirm good/bad emperically.

again: Doug Lawson's articles have the values for the two resistance devices, IIRC.

Good luck! Post results. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
Rick_Stevens said:
So, the best operating temperature is half full? /bcforum/images/%%GRAEMLIN_URL%%/grin.gif

R.
Click to expand...

ROFLMAO !!!

I've spent more time tinkering with fuel gauges than temp gauges so I don't know the resistance range for temperature senders. I believe there are several calibrations Smiths used. On the Mini for instance, they used 3 different combinations of senders and gauges over the years and you have to get the right sender for the right gauge. Of course, this was never properly documented.

As the DR mentioned, if you supply one side of the gauge with 10V and ground the other terminal, the gauge should move up to HOT (or Full).

The article I put together is about the voltage stabilizer and you can get a copy of it at:
https://home.mindspring.com/~purlawson/files/SmithsVoltageStabilizer.pdf
 
Doc:

Is that un alves, ou orths, or our ghts?

/bcforum/images/%%GRAEMLIN_URL%%/wink.gif

Patrick
 
Sadly, I must admit that was undersrood, Patrick... 'ght's, I b'leve. /bcforum/images/%%GRAEMLIN_URL%%/smirk.gif


I remember reading resistance figures on the senders somewhere, thought sure it was your info, Doug.
Now I gotta "go fish" I s'pose.
 
Which brings me to something I have been wondering...I think my sending unit in the gas tank is bad. How empty must the gas tank be to safely pull out the sending unit? Or, for you optomists out there, how full can it be when I pull the sending unit to not to spill out?

Bruce
 
If it's got less than a quarter tank and you jack up the right side for access, the "tilt" will allow you to yank the sender wirhout losing fuel. With the wheel off you can just about WALK in, under there and do it. Youes is a "modern" retaining ring type. A good thing to do is clean all the dust/dirt away from the area first, then apply some "weasel pee" (PB Blaster, etc.) to the ring lip, ID and OD. GENTLE taps, alternating on the three tabs should have it out in minutes. I use a blunt brass drift instead of steel for superstitous sparky reasons, too. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

EDIT: It may be a good idea to have a new O-ring seal on-hand. On reinstall, Permatex Hylomar (very) thin-filmed on the O-ring will seal it well.
 
Like the good DR said, it's a good idea to have a new rubber seal for the fuel sender. If you re-use the old one, you can use the sealant he recommended, Aviation Form-A-Gasket, or Permatex 2B. DO NOT use silicone RTV of any type. RTV is not at all compatible with fuel.
 
OK...thanks...looks like this job will have to wait until spring, when I can run some gas out of her. I replaced the tank and sender three years ago and the sender stopped working after a year. I haven't been sure how much gas was in it and wondered how low it had to be...thanks.
 
If you download the PDF I provided the link to, there are steps in it to walk you through basic troubleshooting of the fuel gauge. That may help you identify if the problem you currently have is with the relatively new sender, the wiring, or the gauge.
 
dklawson said:
If you download the PDF I provided the link to, there are steps in it to walk you through basic troubleshooting of the fuel gauge. That may help you identify if the problem you currently have is with the relatively new sender, the wiring, or the gauge.
Click to expand...

I did that, thank you...identified the problem...now I am working on the solution.
 
and
 
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