New fuel sending unit

[barracudadave67]

I just received my new 5/16 sending unit I ordered thru Jegs. It was drop shipped from the distributor in Texas. It Jegs PN189-GT09-661S. It is not Chineseum. It's made in Tiawan.

I did on "ohms test" on it, and this is what the readings say. L (full tank) 8.2 Ohms
M (1/2 tank) 34.3 Ohms
H (on empty) 75.8 Ohms
This is just reading it new out of the box. I ask this cause I am wondering if anyone else has done this, on a new unit, and what readings you got.
I know aftermarket senders do not read right, but these Ohm readings seem pretty close to me. Maybe it will work closer to normal, tho I bet the least I will have to do is adjust the float.
This unit has a brass float like the originals.
Dave

 

[694spd]

My factory one read 11 ohms to 78 ohms, so pretty much in the ballpark.

 

[RedFish]

The middle of the scale is where aftermarket is wrong. All OEM gauges and senders operate on a 80-10 range. A calculator says half way between 80 and 10 is 45 but the OEM gauge doesn't work that way. As the resistor wire in a thermal gauge heats up, its per inch and/or total resistance changes. So a proper non linear sender should signal approx' 34 ohms at 1/4 range, 23 ohms at 1/2 range, approx' 15 ohms at 3/4 range.
8 ohms really is too low in my opinion. It could overheat and damage a gauge, especially one that is aged.
Put you meter leads together to see what resistance there might be. 1 ohm in the meter/leads means a 7 ohm sender if that makes sense.
I'm sorry if this is TMI.
Bottom line, we have 2 choices...
We spend more coin to have a OEM sender properly restored or we buy a meter match module to alter the aftermarket senders signal to the gauge.
A aftermarket gauge might be a 3rd choice depending on what inst' panel you have. Good luck with it.

 

[kiss]

Make sure the pickup tube reaches all the way to the bottom of the tank also. Chances are you'll have to bend it down a lot.