22. Sex Talk

Molex Plug is a brand name that has become a generic term for a type of multi-wire electrical connector, much like Scotch Tape and Band Aid have become generic terms for their products. From now on I will not capitalize molex unless I'm Talking about plugs made by Molex. What I'm talking about here is the Radio Shack version which they call an "Interlocking Connector". If you go into any Radio Shack and say "molex plugs" they will lead you straight to them.

To describe and differentiate between all sorts of connection parts the sexual terms "male" and "female" are used. It is generally understood that the plug on the lamp cord is male and the wall receptacle is female.

However, with molex type plugs, descriptions are much more in tune with the present, where no one seems to know or even care what words like male, female or marriage mean.

Designation of pin connections are conventional: bullet shaped male fits into hollow circular shaped female. However, descriptions of connectors themselves are much less precise. "Female" connectors are supplied with female pins, but can use male pins or any combination of female and male pins. "Female" connectors fit inside of "Male" connectors. In common usage that makes "Female" connectors plugs, and "Male" connectors receptacles.

On their package, Radio Shack clarifies (?) the situation with the following statement:

"Male pins are normally used in the plug, female pins in the receptacle. They can, however, be interchanged to provide a great variety of polarization combinations when similar connectors are used adjacent to each other, and when wire leads are not otherwise polarized." (Emphasis mine.)

If that is true, why are plugs supplied with female pins and receptacles supplied with male pins?

Packages containing plugs and female pins are labeled "Female Interlocking Connector" and packages containing receptacles and male pins are labeled "Male Interlocking Connector".

I'm so confused.

21. Wired

So, why would a septuagenarian suddenly decide to rewire a car that has been running without any electrical issues for more than ten years?

Since the last rewire was completed a stereo system, an overdrive and cruise control have been added on, but not integrated into the existing wiring.

The previous wiring system did not account for removal of parts for replacement or access. The battery was located behind the driver's seat and was difficult to service and remove. It was nearly impossible  to remove the dashboard and I have an inner ear problem which makes me sick when I lay on my back for more than a few minutes.

It always annoyed me that when the car was last rewired, they went against my wishes and moved the control panel from behind the seat to the left kick panel. It was hard to work on when I was sixty, let alone now.

The existing wiring did not have a master fuse for either the battery or alternator.

The existing wiring panel (American Autowire) used Wago "Cage Clamp" connectors which grab the stripped ends of the wires and in my experience are prone to poor connections.

 

The car is destined to go to my daughter for her or her boys to use, which magnifies the importance of  safety related concerns.

Since I am now retired, I needed a relatively long term project to occupy my time.

Convinced?  I am. My wife isn't.

 I looked at wiring kits from the usual suspects (Painless, EZ Wire, American Autowire, etc.) and found a lot of features I didn't like. I'm not fond of  factory terminations to the panel. The manufacturer can't know which circuits I need. I have no need for a tiny crowded control panel. Painless Wiring had the only kits I found for behind the seat mounting.

The ISIS intelligent multiplex system is intriguing, but pricey. I sounds like it would shorten installation time, which would make economic sense for professional builders, but was not what I wanted.

I chose to use a Coach Controls Coupe-23 wiring kit. It has 23 circuits (18 fused). There are 14 relays including a 40 amp fan relay to allow low current control of high current systems. The control panel is good looking and well designed, and uses screw stud terminals for connections. The panel can be mounted behind the seat, although it is not specifically designed to. Coach Controls has more than ten years experience in race car wiring systems. They design and build their products in the United States. It does require buying an open barrel crimping tool. Don't you hate it when you have to buy tools? Me neither.

The objective of this project is to rewire my '39 Ford coupe so that the wiring is safer, neater, more logical and so the car is easier to work on. All circuits including the battery cables will be fused. All grounds will be attached to the frame, and multi-conductor plugs or quick disconnects will allow easier parts replacement.

In preparation for mounting the panel behind the seat, I removed the damaged original pressed board divider between the trunk and the passenger compartment. (See previous chapter.) 

The first thing I did was move the battery to the passenger side, still behind the seat. This is not ideal, because battery fumes can be released into the passenger compartment, but this has not happened in ten years of driving the car, so I feel that the risk is tolerable. I discovered that the master disconnect (kill) switch was on the ground cable. That's a good thing. If a tool touches the plus terminal and the body or frame when the kill switch is in use, there is no continuity, no short. In the process of moving the kill switch, I discovered that while the ground cable was made from 1 gauge welding cable, the much longer positive cable was 2 gauge. The plus cable should never be smaller than the minus cable, even if they are both the same length. The 13 foot length of the positive cable exacerbates the problem. Since the 2 gauge cable handled the load without issues, I increased the size to 1 gauge (red) welding cable. 1 gauge welding cable is made up of 780 strands of .01" wire, is much more flexible than standard battery cable, and the insulation is much thicker.     

During the wire removal stage of the project, I discovered several interesting wiring innovations.

 

 

 

These reinforced my decision to rewire.

Before I started wiring, I made a wiring list. This is a working document which I revise as I discover wires needed which I forgot to include, unintended duplication, etc. The wiring kit included a large two-sided plastic coated generic wiring diagram, and there were additional more specific diagrams on line. The on-line diagrams are restricted: you can print them but not download them. So I printed them, then scanned them into the computer as jpeg files and modified them as needed. For instance there is the following published diagram for front parking lights that do not turn on with the headlights

 which I Photo Shopped to

 

After completing the headlight wiring, I decided to test it. The taillights and parking lights lit, but the headlights would not. After a lot of review and head scratching, I wondered if some other circuit in the Coach Control Center was involved. I touched 12 volts to the ignition switch lead and the headlights came on. The system is designed so that the headlight circuit is only activated when the ignition is on.

Who knew?