Oil sending unit wire

[eoseitz]

I bought a new engine harness from corvette America (or central) can't remember. I had a local shop hook it up and everything is running great. The previous owner took out the oil sending unit and put a crappy sunpro mechanical gauge in the car. I'm attempting to put it back to stock, but I ran into an issue. My haine's manual says the wire to the oil sending unit should be tan. However, the wiring schematic I bought says dark blue. I only see one dark blue wire in the general area of the sending unit. I believe it goes to the washer pump. I have a 74 L82. Any idea where the oil sending unit wire is and what color it should be? My wiring schematics show correct colors on everything else. Someone on here pointed me to a reputable person to buy them from online.

Thanks.

 

[eoseitz]

I think I found the wire. It's under the shaft for the steering wheel. There are actually 2 wires going to it. A white and a black. I'm guessing white are for cars with a dumby light. The gauge isn't moving though. I'll post a pic of the plug. I have 2 spare oil gauges. Is there a way to test these outside of the car?

 

[eoseitz]

 

[SVO]

Corvette's of this era never had a "dumby" light.

 

[eoseitz]

Corvette's of this era never had a "dumby" light.

What's the 2nd wire on the plug for then? grrrrr. Maybe I have the wrong plug still. Does it look correct? Should my oil sending unit have two terminals on it? How can an easy fix always go so wrong. lol

 

[SVO]

To be honest, I thought that '74 Corvettes still had a mechanical oil gauge. I would guess that the black wire would be a ground. I would need to find a '74 wiring diagram to see. Let me do some checking and see if I can find you a better answer to your question.

Bob

 

[frank_nesta]

It is a single wire, mine is green (1977), and comes out of the harness right under the steering column in the engine compartment. I hope this helps.

 

[eoseitz]

It is a single wire, mine is green (1977), and comes out of the harness right under the steering column in the engine compartment. I hope this helps.

I found the wire. It is under the steering column and dark blue. My gauge is working now, but it twitches a bit. Should it be a gradual increase or decrease when you rev the engine or should it jump? At idle its staying around 30ish psi.

 

[frank_nesta]

I found the wire. It is under the steering column and dark blue. My gauge is working now, but it twitches a bit. Should it be a gradual increase or decrease when you rev the engine or should it jump? At idle its staying around 30ish psi.

No twitches from mine. It jumps when I rev the engine, but stay there.

 

[6880 Mike]

As you have learned, the Hayne's and Chilton's manuals are much too C3 generic to be 100% reliable. Use the GM chassis service manual and AIM; they are model year specific.