2 fuel gauge-related questions

[Guest E.Murray]

The fuel gauge hasn't worked in my car since I bought it, so I finally got around to looking at it this weekend. The sender is in good shape and the wiring is good (I can move the arm on the sender and get a changing ohm reading at the gauge connections). It looks like I need a guage, so I bought an Autometer 2315 (old Ford unit which should work good). I have 2 questions:

1. I can't get the wires back on the sender. They were hard to get off (31 years in place made them a little stubborn...go figure) and I'm afraid I sprung the little connectors. I haven't been able to find new ends to put on the wires that will attach to the sender terminals. Any ideas for a source or other option?

2. I took apart the old gauge and it looks fine. There are 3 connections at the back for the fuel gauge: 1 for the power (ignition), and 2 for the wires from the sender. I know that I'm getting 12 volts and the ground is good. The resistance across the 2 sender terminals is 110 Ohms. Any idea what this ought to be?

[Pop N Wood]

For the connector, I would scour a JY for a 2 wire plug in connector then solder/shrink wrap it in place.

 

As for the gauge, how do you know the gauge is bad and not the wiring between the sender and the gauge? You have two options, either check the wiring, check the gauge or both.

 

To check the wiring, disconnect the sender wires at both ends (the gauge and the sender). Next twist the wires together at one end. Now take your ohm meter and check 1) the resistance across the wires and 2) the resistance between one wire and a good ground point (clean metal). If there is a large (> maybe 20 ohms) between the wires, a wire is broken. If the resistance to ground is low(say less than 20 kiloohms) there is a short to ground. Either problem could kill the gauge.

 

To check your gauge, hook it up directly to the sender with some jumper wires and hook up a battery to the power and ground. Now manually move the sender and see if the gauge responds. I would also do a check of the sender to make sure it is not shorted out to ground.

 

I have found that most electrical problems are due to bad connectors or wires shorted out to ground. Occasionally a component fails, but probably 95% of the time it is a connector.

[Guest E.Murray]

I checked the sender and wiring together by using the ohm meter at the gauge terminal end of the wires (with the gauge disconnected, obviously) and got good ohm readings (10-90 ohm range), so this tells me both the sender and the wiring are good, unless I'm missing something.

As far as the connector, the problem is that I can't get the wires connected to the tiny "mushroom" terminals on the sender. The stock connectors clip over the terminals and grip them to get a good connection. Once I pulled them off, though, the part that grips bent and doesn't hold any more. I went to a local electronics store looking for something similar and had no luck. I was hoping someone else had run into the same problem and knew of a source or work-around for the oddball connectors. Thanks for the suggestions.

[COZY Z COLE]

Take a look at this write-up.......

 

http://www.atlanticz.ca/zclub/techtips/injectors/connectors/index.html

 

LARRY

[Guest E.Murray]

Hmm. Those look pretty similar to what I'm needing. Hard to get an idea of scale from the pics (the terminals on the sender are pretty small), but dang if it doesn't look like I might be able to make those work. Thanks for the lead.