How does the AC wiring harness enter the engine compartment?

[davepl]

From the schematic it looks like it goes through the evaporator case and out a grommet in the case itself. Except I can't find one. Worse, I already have the heater core in so it might be a fun one to fish.

I'm speaking specfically of the green and black pair on a packard connector that plugs into the compressor, and that has a diode soldered between the two posts of the connector.

Thanks for any 'leads'!

-Dave

[FirstOwner69]

Why couldn't have asked that about 20 hours ago? I'm now about 150 miles from my truck.

The wires do not come out through the evaporator case. They come through the firewall through the same grommet as the A/C vacuum limes as I recall. The hole is in the firewall to the right (when viewed the front) of the evaporator case near the top of the bell housing recess in the firewall at about 11:00. Here's a picture, but I don't think it'll help much. I don't know if you can see it, but on my computer it looks like there is a green pixel at the point where the vacuum hoses and wires come through the firewall. The wires are encased in a fabric loom and are strapped to the heater hoses through the engine compartment. If you look at the picture I posted yesterday in your thread "The Impossible Air Conditioning Connection" you can see that routing.

Edit: Added a zoomed in pic with showing the fabric loom routing to the compressor.

Hope this helps.

Jim

[turp mcspray]

Here is a pic of an untouched factory route. I have seen some that have the wires going under the a/c housing, and others that run them over.

[FirstOwner69]

Originally Posted by turp mcspray

Here is a pic of an untouched factory route. I have seen some that have the wires going under the a/c housing, and others that run them over.

That's a better picture that clearly shows what I was trying to describe. To correct something I said in my previous post, I believe the wires were wrapped as Turp's picture shows all the way to the compressor rather than in fabric loom. I recall running them in loom for appearance sake since I had some extra. Mine ran under the evaporator case then along the heater hose as stated in my first post.

[Lee H]

I went through my deconstruct pictures, mine was the same as Turp Mcspray's.

[davepl]

Thanks!. I was apparently looking at some weird diesel or V6 or who knows what configuration in the assembly manual.

From the assembly manual it looks like they're supposed to run under. I may be using the wrong one of those two holes, I'll have to run out and double check.

I wish our assembly manuals SAID what option or feature that page describes (like my Impala and Camaro ones do). The index this board put together is super-helpful, but it'd still be handy.

[davepl]

OK, I'm at a loss here. Below you can see the original photo I took during disassembly and then the current state of the truck. I guess the body shop must have covered the hole, but I really have no idea why. I'm going to have to open it up just for the cable control I think.

[FirstOwner69]

Edited: Guess I didn't do a good job of reading your post.

That's what I'm thinking too. I believe you need the sealed hole for the cable. Maybe they plugged it because it was ragged and forgot to drill it prior to paint. You'll have a tough time finding that grommet though. If you find one let me know where.

Jim

[davepl]

They probably filled it because the grommet was missing and it was just packed with bathtub caulking, it looks like!

What's special about the grommet? I did get one with three holes and little metal retaining clips, but that's the only fancy one I've run across.

[Andy4639]

Factory 1971 shop manual shows it like this.






Here is the inside the cab wiring.

[FirstOwner69]

Originally Posted by davepl

What's special about the grommet? I did get one with three holes and little metal retaining clips, but that's the only fancy one I've run across.

The grommet I could not find is the single hole grommet that the cable passes through. The one that goes in your plugged hole. The 3 hole grommet is for the other hole which the vacuum lines and harness go through. Both grommets are clearly visible in turp mcspray's picture in post #3.