Trips to Germany and that blasted Christmas holiday conspired to keep work from progressing, but believe it or not, the project still goes on. We all knew the engine bay wiring would be a horrendous train wreck. After all, it's a forty four year old car that's undergone at least one engine rebuild and who knows how many shade tree mechanics. With the mild weather we had last weekend, I decided it was time to dive in head first and find out how much pain to look forward to.
After removing that big old Holley and putting it to the side, I decided the loom that runs along the top of the right bank would be the best place to start my adventure. Lots of heat in there, a hacked together wire cover, lots of electrical tape... it all pointed to a good old time. Remember kids, whenever you do work on the electrical system, don't forget to unplug the battery, bad things could happen if you don't. With that word of caution, let's take a look at what was found.
First thing to notice is the main ground cable. Let's make that two main ground cables because the original was chopped off right under the radiator overflow tank. Why? Who knows, perhaps it was cut in jest. Maybe they were just lazy, that bolt is hard to get at and takes at least a minute with a box end wrench to remove... why not just hack the cable off and put a new one on the lower intake retaining bolts? There, that's much easier (wankers).
After stripping off the split cover it was quite apparent that the last guys that got into this harness weren't too fond of doing wiring correctly. Lets start with the oil pressure sensor. There were at least four places where the wire had cracked or broken and had been twisted back together and held in place with electrical tape. Ignition coil lead? Well, the insulation is only a little burned in this one spot; just wrap that up in electrical tape. There, all better now. It didn't take much digging before mystery wires starting popping up. I was able to determine that this red and blue wire needed to go to the temperature sensor on top of the intake manifold - who needs to have that functional? There's also a gray wire that I haven't got a clue on.
The amusing part about all of this is how most of it could have been avoided. From the condition of existing cotton and tar harness insulation, it's a fair bet that the the stuff started falling apart along this section of the engine, virtually inevitable with that stuff. The fix should have been some form of heat wrap that protects the wires as well as holds them together. Instead the old standby of the el-cheapo split wrap was put in place, thus ensuring heat damage and nice brittle wires. The plan of attack will be to save the harness ends and solder in replacement wire as close as possible to the wire color code. A lot of the connectors are getting tired, so those will get replaced while we're at it and the whole mix will be wrapped in heat shrink where it makes sense. The problem right now is how to prevent a repeat of fried wire syndrome. We'll just have to see what the auto parts store has to offer when it comes to heat protection. Any suggestions?