Ohms readings from sending unit...help

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Tony Fields

Tony Fields

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I'm trying to sort out my fuel gauge as to why it doesn't work.

Can someone please tell me what setting I should use on the
meter below to read the ohms at my sending unit in the tank.

Also where do I clip the red wire and black wire from the meter?

Everything I have tried only resulted in fluctuating numbers on
the meter that return to zero. I want to make sure my new sending
unit is working correctly before I go any further.

Thank You!
 

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Yup, Tank empty 52-55 ohms, tank full 5-8 ohms. red wire on sending unit wire connector, black on sending unit ground or fuel nipple right at the unit before the hose to the car fuel line. Also check that the battery (usually 9volt) is good in the meter.
 
Turn the knob to the right, clockwise, into the black area with white numbers, the upside down "U" is the "omega" symbol, meaning ohms. Set that on "200" This means the meter will measure ACCURATELY up to 200 ohms, and whatever you read in that range will be "direct reading," and depending on how accurate that meter is, it might say 73.0, or 73.5, or just 73, when reading "about" 73 ohms

It does not matter, IN THIS CASE whether black or red leads are interchanged. As above, one goes on the wire connection, the other goes on any of the metal of the mounting flange.

Make SURE you get a good connection
 
demon seed said:
Yup, Tank empty 52-55 ohms, tank full 5-8 ohms. red wire on sending unit wire connector, black on sending unit ground or fuel nipple right at the unit before the hose to the car fuel line. Also check that the battery (usually 9volt) is good in the meter.
Click to expand...

Thanks Terry......but what setting do I turn the dial to?
 
67Dart273 said:
Turn the knob to the right, clockwise, into the black area with white numbers, the upside down "U" is the "omega" symbol, meaning ohms. Set that on "200" This means the meter will measure ACCURATELY up to 200 ohms, and whatever you read in that range will be "direct reading," and depending on how accurate that meter is, it might say 73.0, or 73.5, or just 73, when reading "about" 73 ohms

It does not matter, IN THIS CASE whether black or red leads are interchanged. As above, one goes on the wire connection, the other goes on any of the metal of the mounting flange.

Make SURE you get a good connection
Click to expand...

Thanks Dart......off to the garage....dial to 200k or the plain 200?
 
Between my bad vision and my POS monitor I cant tell which hole in the meter is which. So here's what you do Turn the meters switch to 20 ohms scale. Put your lead contacts together. The digital display should go to zero breifly then change to something like .5 or 3.5 ( varies ) which is the resistance in the meters leads.
If you dont get something like described, leave the center probe where is is and move the far right to far left and repeat. Once you know you're seeing zero ohms resistance or close to it, you're ready to check the sender.
Either probe on the senders terminal post and the other probe on any chassis ground.
73 ohms is empty, 10 ohms is full.
If you were calibrating an instrument you would need to calculate in the meters resistance.

Foryour general knowledge, start on the 20 ohm scale and get a reading then change the scale . Each added zero will move the decimal point one place.
And for the rest of you wiseguys, Tony never said he had the sender out and on the workbench, so a good ohms reading doesn't dianose a failed gauge when the ground is on the sender itself.
I'm done
 
Ground the blue sender wire. If the you pin the gauge, replace the sender more than likely.

With your OHM meter put the pos on the stud on the sender the black to ground. The sweep is 73-9.6 ohms.
 
That's why I don't like digital meters for senders....they jump around a lot unless you get a perfect connection. The old analog ones are more forgiving and act more like the actual gauge.
 
cudamark said:
That's why I don't like digital meters for senders....they jump around a lot unless you get a perfect connection. The old analog ones are more forgiving and act more like the actual gauge.
Click to expand...

I have a couple of Flukes which have a VERY useable bar graph, but I DO also have a couple of old "old school" meters

I'm old enough to remember when we didn't HAVE digi meters, and when they DID appear, they were big, heavy, benchtop models that cost a fortune.
 
My sending unit checked out ok. I ordered me a new Auto Meter gauge
part no. 2642 this evening. I've also had to replace the amp meter.
I'm tired of these old gauges going bad. I think there is something wrong between
the tank sending wire and the gauge. If necessary I will replace that wire also.
 
Tony Fields said:
My sending unit checked out ok. I ordered me a new Auto Meter gauge
part no. 2642 this evening. I've also had to replace the amp meter.
I'm tired of these old gauges going bad. I think there is something wrong between
the tank sending wire and the gauge. If necessary I will replace that wire also.
Click to expand...

Have you got that little metal clip on the sender fuel line. It grounds the sender by clipping on the fuel line at the sender and the main fuel line right where that short 3" chunk of rubber line connects the 2 lines.

http://chucker54.stores.yahoo.net/moseungrst33.html
 
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