The Snakes Alive CMP Wiring Project

[Jacques Reed]

Originally Posted by Dave Schindel

just wondering if anyone has found a supplier for bullet connectors for the F15a cab 11 ? The old ones are all crimped on so can't be reused . Need 2 different sizes at least. The big ones are .240 OD bullet and the smaller ones are .190. I am using original cloth type wire of the correct color and would like to make the proper connections. Any ideas?
dave

Hi David,

Just stumbled upon this company, The Brillman Co. in Virginia USA. On page 16 of their downloadable catalogue are two sizes available 0.156" and 0.180" diameter. Perhaps the 0.180" would suit.

Great stuff in the catalog. Cotton braided covered wire with various traces available and US made quality to boot. There is only one source of that type of wire here in Australia.

Pity I am so far away and the freight is much more than the cost of the items. I wanted to visit a few more Civil War Battlefields so perhaps that is a good excuse to go to Good Ole Virginny!

Cheers,

[Jacques Reed]

Good Day,

In the process of renewing some wiring I noticed some errors in my previous post on the lighting panel wiring. I have upgraded the diagrams accordingly.
Basically 16 gauge wire was used for the jumps, lead to the inspection socket, and dash lights instead of 14 gauge wire.

This became apparent when I compared the three wires on the cowl terminal block to the drawing supplied by Keith. see attached. This gave me a good reference point to determine the sizes of all wires on an original harness fitted to a late war dash. Checking good sections of the wires with a vernier eliminated the eye being fooled by colour or light.

As a general guideline, the wiring between instruments, dash lights, inspection socket, the resistor and coil, start button to solenoid, and wires connecting sending units are 16 gauge (same size as high beam indicator wire). Wires for the jumps between the switches are 16 gauge also but attach to 14 gauge wires on the main harness. I believe the reason for this is two wires into a bullet require smaller gauge wire to fit and as the wires are close to the power source and short, the voltage drops are negligible.
Wires to the tail, side, and stop lights are 14 gauge (same size as side light wires). The wire to the headlight terminal on the cowl is 12 gauge but the tails from the block to the two headlights are 14 gauge. The stop light isolation switch out wire is 14 gauge as there is only one wire connected to the switch on the output side. The longer runs to the tail and stop lights require larger 14 gauge wire to reduce the voltage drops.

There may be other variations based on wartime expediency but these sizes are correct as measured on an original harness.

Cheers,

[Jacques Reed]

Good Day,

I have just redone my wiring from the ignition and fuel tank gauge switches in the course of redoing all my wiring. I redid did the light switch panel a couple weeks ago.

The interesting thing I discovered using an original harness for a pattern is the Autopulse wiring. Even though the Autopulse was only fitted to Indian delivered CMP trucks it appears the wiring for it has been fitted to the harness of at least one Australian Ford CMP also. Perhaps one size fits all by Ford.

As per attached photos:
Wire No. 45 is a jump from the ignition switch- out to the Autopulse switch in. When the ignition switch is thrown current to the resistor and the Autopulse input side flows.
No current flows to the Autopulse unless the Autopulse switch is also thrown. So you can run the engine without the Autopulse on but cannot run the Autopulse unless the ignition switch is on.
No. 46 wire is fitted to the main, and lower chassis harness also and terminates near the starter relay with the other tail, stop, and fuel tank sender wires.
No.16 and No. 45 doubled up at ignition switch to resistor and not at No. 30, ignition switch to gauges, as shown in Special Pattern Vehicles diagram. Not the first time diagrams and reality differ.
Again, all wires are 16 gauge except No. 21 which is 14 gauge.

Hope this is of some interest and have a safe and healthy Easter.

Cheers,

[Jordan Baker]

The wiring for the front marker lights, does it go directly to the junction block mounted on the inside of the nose or was there a separate junction closer to the light?

[Grant Bowker]

I don't recall ever seeing any evidence of an intermediate junction block and the diagram in section 2.605 of the parts book shows the sidelights with connectors to suit the central junction blocks. On the other hand, I don't remember seing light assemblies with long wires as replacements - maybe because so many were damaged by trees they were all "field expedient" repaired, extended or whatever... and none left for NOS sales?

[Phil Waterman]

Hi Jordan

I've encountered marker lights with long tails with spade ends long enough to reach the terminal strips up on top of the footwells both sides. Have also bought NOS marker lights with short wire tails about a foot with plug ends for inline connectors.

Cheers Phil

[David Dunlop]

Hi Jordan.

According to MB-C2, the two terminal strips either side of the cowl take headlight wiring only. The circuit diagram shows the two side lamps feeding directly to their switch on the dash. Whether that is a direct, long lead feed from both lamps to the switch, or shorter length leads that get the wire inside the cowl and then connect to fittings on the main cowl section of the wiring harness is unclear.

David