Engine wiring harness question

[Kenneth T.]

On my '71 LS5, no air, the engine wiring harness runs along the firewall to the heater box and then down to the starter. My question is, should the harness be in front of the heater hose or behind it against the firewall.

Mine is in front and I am concerned it seems too close to the exhaust manifold. I have checked my AIM without a clear answer. I also looked at several rererences in the archive, in one case I saw a '71 LT-1 with the harness in front, same as mine.

Any help, thanks.

Ken

[Paul C.]

Re: Engine wiring harness question

I replaced the ignition wiring harness on my 71 LT-1 last year and ran the wires where they were which was behind the ignition shield and then with the vacuum hoses inside the clip and then along the passenger side with the vacuum hoses again. The only wires near the exhaust manifold are those going to the sensors on the block. Do not know if that is correct but I removed the old harness as I put the new one in--so it would be in the same position.
Paul

[Alan S.]

Re: Engine wiring harness question

Hi Ken,
This is what I observed on my 71 SB.
The engine harness turns DOWN towards the starter a couple of inches BEFORE it gets to the heater core nipples. It does this in order to 'lay' under the clip that's riveted to the cowl that is just above where the harness finally turns forward toward the starter. When the harness turns down this early, the electrical leg for the bower motor is actually DOWN about 2 inches when it exits the harness, and comes back UP before it continues on it's way over the heater box (2 clips) and to the blower motor.
The AIM page for the Engine Wiring doesn't show this drop at all, it shows the harness running straight, but this is how my original harness was run.
Does this apply to your BB???
Regards,
Alan

[Kenneth T.]

Re: Engine wiring harness question

Paul,

I am referring to the section that tees downward to the starter, it is a wrapped bundle of several wires. I should post a picture to clarify my question.

Ken

[Kenneth T.]

Re: Engine wiring harness question

Alan,

Yep, I think the light just came on. There is a clip there holding the battery cable. I now think that the harness should also use this clip. I may have to pull it a bit to get there. I will try later as it is a nice day today and I have the time.

Thanks both Paul and Alan, I will let you know.

Ken

[Alan S.]

Re: Engine wiring harness question

Hi Ken,
I believe the clip I mentioned is turned the wrong way for the battery cable to run through it. I believe the last clip on the underbody for the battery cable is in the transmission tunnel, and the next clip is on an engine bell-housing bolt (at least on my SB), and then the clip on the starter solenoid. I hope I'm not mixing SB & BB too much here!!!
Regards,
Alan