Need help identifying loose gray wire in engine compartment near the voltage regular

[Rubatoguy]

I was looking in the engine compartment of my 1971 Chrysler 300 and noticed a loose gray wire by the voltage regulator.
It appears to go into the wrapped wiring. Does anyone know what this wire is for and where it should go?

thank you,
Todd

 

[Big_John]

Goes to the oil pressure light sender.

 

[Big_John]

 

[Rubatoguy]

View attachment 725270

That makes sense since the car had an accessory oil pressure gauge. I will probably have to add a T fitting and get a sending unit. Thank you!

 

[Big_John]

That makes sense since the car had an accessory oil pressure gauge. I will probably have to add a T fitting and get a sending unit. Thank you!

If you look at where the oil pressure sender is, on the opposite side, there is another access plug that works great to screw a sender in.

 

[Rubatoguy]

Oh, Cool! It is kind of hard to see back there.

 

[Gerald Morris]

Oh, Cool! It is kind of hard to see back there.

You can use a Tee or the second, right hand port as you like. Do yourself ONE Favor: use brass fittings for this job. Steel has a way of rust-welding itself into the threads, making life difficult if you ever want to remove it. I'm currently having to drill AROUND a snapped extractor, in hope of removing IT, then, using a much larger and stronger extractor, heat, and more exotic penetrant/lubricants, turning the iron plug out of the iron block. I dig the pic Big John provided. Note that the oil galley plugs in that appear to be brass. I use a tee on the lefthand port back there, simply to accommodate the sending unit wire length and the 1/8" mech gauge tubing I use with that. I like to know my oil pressure even sans electrical instrumentation.

 

[Rubatoguy]

You can use a Tee or the second, right hand port as you like. Do yourself ONE Favor: use brass fittings for this job. Steel has a way of rust-welding itself into the threads, making life difficult if you ever want to remove it. I'm currently having to drill AROUND a snapped extractor, in hope of removing IT, then, using a much larger and stronger extractor, heat, and more exotic penetrant/lubricants, turning the iron plug out of the iron block. I dig the pic Big John provided. Note that the oil galley plugs in that appear to be brass. I use a tee on the lefthand port back there, simply to accommodate the sending unit wire length and the 1/8" mech gauge tubing I use with that. I like to know my oil pressure even sans electrical instrumentation.

Great idea. I did take a second look and discovered there is a second port, which I think I will use rather than a T. I'll post a photo when I manage to finish.

 

[Gerald Morris]

Great idea. I did take a second look and discovered there is a second port, which I think I will use rather than a T. I'll post a photo when I manage to finish.

As you like. I found that for the purpose of hooking up the old sender wires AND a mech gauge, a tee proved a little easier, but using that RH port has its advantages too. Good luck. I probably will use a stainless steel line when the copper gets vibration brittle.....