When I changed over to the electronic ignition I found that the engine gauge feed wiring was stiff and brittle. I wanted to replace it before any problems happen.

This is the original harness on the basement workbench after being removed from the car. It's covered with blue overspray since it wasn't removed or covered up when the motor was repainted. You can see that the heat insulation wrapped around the center wire that went to the coil is deteriated.

I ordered a new (repro) engine gauge wiring feed and also the oil pressure extension lead. When I got them I found out that the repro harness was too short to reach the coil plus the oil pressure lead had the wrong plugs on it. I decided to try ordering another engine gauge feed from another parts supplier I deal with. When it showed up a few days later from National Parts Depot it was exactly the same harness I had originally got from Mustang's Unlimited. I did not reorder the oil pressure lead.

Here's what the oil pressure extension lead looked like when I got it. Neither plug would work with my car and the other harness. My oil sender needs a spade connector, not the press on one the harness has. The wire color of white with a red stripe was correct though and matched the original harness.

Here you can see one of the new harnesses laying behind the original one. Both firewall plugs are lined up but you can see how the repro one is much shorter. The original one continues right out of the picture's range on the right side.

That's a van door motor on the bench next to the Krylon can and isn't part of this job. It's a spare from a FIRST robot with the team I'm on.

I decided to make this work and make the new harness look as original as possible. Instead of returning one of the harnesses I was going to cut it up and splice it into the other one. The harnesses are wrapped with tape in the center which was the perfect place to splice them and no one would ever know.

I stretched out the original harness on the bench so I could copy it's length as I worked on the new one beside it. I took both harnesses and removed the tape from them. I cut one of them in the center where the tape would hide it.  With the firewall plug side of this harness laying next to the original and lined up with it's firewall plug, I grabbed the second harness and laid it out with the three plus lined up with the original one. Where the second harness met the first one is where I cut it. This now gave me the correct length that the original one was. I stripped the wires, slid heat shrink tubing down them out of the way and them soldered them together. Next I slid the heat shrink back up to the solder joints and used my heat gun to activate it. All the wires were heat shrinked individually to prevent shorts between them then one larger piece was shrinked on top of the three smaller ones to protect them even more. Now I rewrapped this harness with electrical tape like it had been and so it would match the original one. The last things I had to do was change two of the plugs so they would work. I cut off the original oil sender and coil plugs. I installed a spade connector on the oil sender and the coil wire got a ring terminal so it would work with the stainless steel nuts I had used when I converted over to electronic ignition.

Here's what the new harness looks like next to the original. You can't tell that it had started out as two separate identical harnesses, it now matches the original one. Some of the cut off remains are visible between them.

The new harness was installed on the car with no problems and stands out nicely against the engine like it should instead of being painted blue and blending in. What a relief knowing that I don't have to worry about this harness now. I'm glad I had discovered how bad the original one was before any possible problems started.

The new "custom made" engine gauge feed harness really looks good. It also makes the engine look a little more detailed.......an added bonus :)

HOME (main page)