Changing out a engine wiring harness

[Lyndon S.]

If I have to change out my engine harness to get my TCS/CEC working, how hard of a job is that to do while
the engine is in the car? Has anyone done that?

[Jack P.]

Re: Changing out a engine wiring harness

Not very hard. It is a simple harness, you can see the harness listed and shown on all the usual vendor sites. Just lay it out next to the old harness on car and as you remove plugs from the old harness, you can just plug in new one. Should not take more than a few hours. You will need to be flexible with your hands on the headlight plugs.

Clean all connections before plugging in new sockets. Only have to go under car for starter connections

Jack

[Larry M.]

Re: Changing out a engine wiring harness

Lyndon,

I changed the harness on our '72 while the engine was out of the car; but I agree with Jack that with the engine in place, and laying out the harness in an approximation of it's final routing, it shouldn't be too difficult.

I did encounter one small surprise, regarding the bolt that holds the bulkhead connector. Details here: https://www.forums.ncrs.org/showthre...7273#post17273

[Larry M.]

Re: Changing out a engine wiring harness

Lyndon,

I just remembered that the engine was in the car when I replaced the harness in 2000. When the engine was out, several years earlier, I simply re-taped the harness.

So, yes, it is easily possible to make the change with the engine in.

Larry

[Alan S.]

Re: Changing out a engine wiring harness

Hi Lyndon,
I agree that the engine harness is probably the easiest of the four to replace.
It's the only harness I felt I needed to replace on my 71. The only problem I had was that the 2 wires (dark blue/yellow) for the wiper pump were about 2 inches short. I had to be careful just where the harness was positioned as it passed under the wiper motor so the 2 connections could be made.
Remember you also need to buy the short CEC jumper harness that runs from the thermal switch in the rh cylinder head to the engine harness.
Over the weekend I took a picture of the reversing relay and the delay relay mounted on the firewall. I'll include it so you can see them. The delay relay (towards the rear) is one version, there's also one that looks like a tiny toaster. I'll also post a picture of the thermal switch jumper wire
I hope the new engine harness will get you on the way to having the cec system working! Using Jack Humphrey's article from the RESTORER really helps!
Regards,
Alan