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wiring diagrams/ wiring harness 101 questions

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ichthos

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I admit that being a novice in restoring my Bugeye has made this restoration one big learning experience. Most of the time I have enjoyed the lessons. After a long restoration, I will finally be done this summer. I have a few questions concerning wiring diagrams and wiring harnesses I am hoping you can help me out with.

1) When one buys a new wiring harness, why don't they come labled so that you know where each wire goes? Is this considered so obvious that the manufacturer doesn't think this is necessary?

2) On the wiring diagram, why isn't it more obvious where wires go? For example, it will show three wires going to a light, but not show where each goes. Is this just a lack of knowledge on my part in reading the diagram?

3) What do the very small "hot dog" shapes mean in the wiring diagrams? For instance, in my wiring diagram there are two of these between the heater switch and heater motor.

4) Are there any tutorials on how to read British wiring diagrams?

Any help is greatly appreciated as always.

Kevin
 
Hiya Kev... I just posted a general explanation in your t-signal thread.

I'm drawin' a blank on the "hot dog" symbol, tho.

<scramblin' for a diagram>

<span style="font-style: italic">
EDIT: Ah-ha! Those are th' "Lucar" connectors. Metal sleeves covered in rubber tubing. They come as single, two, three and four wire versions.</span>
 
ichthos said:
3) What do the very small "hot dog" shapes mean in the wiring diagrams? For instance, in my wiring diagram there are two of these between the heater switch and heater motor.
Click to expand...

I think they are just the black rubber connectors

ichthos said:
4) Are there any tutorials on how to read British wiring diagrams?
Click to expand...
Moss Motors has an explanation of the color codes in the back of their catalogs. I can email a copy if you don't have a catalog.
Cheers
 
Kevin,
I will try to answers your questions, having just installed a harness in my Be
1. The wires are actually labeled, but only with the colors. The installation is considered to be done by someone who can read a wiring diagram and "ring" out which wire goes where on the device, like a switch.
2. Yes, probably you are not comfortable with wiring diagrams and how electricity works. It will come with time and prbably some frustration.
3. Those "hot dogs" are the bullet type connectors which unfortuately holds the electrical system of our british cars together. The two bullet connectors between your heater switch and the heater are as follows: The one connected to the switch is located under the dash and is on a wire attached to the heater switch. The wire between the two connectors is the wire harness(green/black) which runs from the back of the dash into the engine compartment and exits next to the blue wires from the headlight dipper switch connections. The wire closest to the heater is attached to the heater motor. (This is how my wire harness is, yours may differ).
4. Moss has a book called Lucas Fault Diagnosis, might try that, although I have not read it. Good luck Scott in CA
 
What year and flavor of Spridget do you have?

The early cars are pretty simple, and the diagrams are similarly easy to deal with. Some of the later ones are nightmares, even for a committed electrogeek like me. Then, of course, they're shrunk to fit on a single Haynes-manual page.

I have seen people on the web or ebay selling color-coded, enlarged wiring diagrams, which probably would be a big help. I can't remember more specific info on this, but maybe with a little searching you can find something better than what you're using. That might be a big help.

I know, if you haven't dealt with electrical issues, it may seem a little daunting. However the upside is this: electricity is 100.0% predictable. If you have a carb problem, you can spend months fooling around with jets and needles and such before you get it going right, but with an electrical problem, you just get a multimeter and do some checks, and the problem becomes obvious right away. Just requires a little knowledge and a logical troubleshooting methodology.
 
Look on the back few pages of the latest MOSS Catalog. Complete wiring code guide that is really, really, simple to understand courtesy of John Twist. Digest this and then get a copy of a schematic of your car's wiring diagram. It's plumbing and it you think of it that way is easier to understand.
 
I have a 69 TR6, which I wired with a diagram from a Haynes manual a few years back. That was the first time I have hooked up a harness before. I didn't have any problems with that wiring. I know Bugeyes are supposed to be simpler, but quite frankly I would be in trouble without help from forum members for this job. Oh, I have a stock 1960 Bugeye. I am in the process of putting it back together after a long restoration process. I bought one of those colored charts, and I have still found the original diagram more helpful. I wish there were someone local who could show me how to do some of the simple checks people refer to. Normally people get frustrated trying to explain to me how to do these checks on the forum. I would guess this is something better explained by doing a hands on explanation. One reason I bought this car was to learn how to work on a car myself. I have a long way to go before understanding how to install and read the wiring diagrams.
Kevin
 
Be at ease, Kev. We're not runnin' out on ya!

A BIG help for you would be to use a VOM (Volt Ohm Meter) and/or a 12V test light for sorting things out. The VOM can be used to test and sort wiring without battery connected. Some extra-long lengths of wire as "extensions" for the meter leads can be clipped to a wire's end at the front of the car as you poke 'n prod at the other end. Steve said it: a logical troubleshooting methodology is key.

I'm sure if you were geographically close, any number of us would be willing to give hands-on help, too. I know I would.

Don't allow it to frustrate ya, it'll sit patiently while you have a beverage of choice and mull over the issue... do it as you have been, one gizmo at a time. :thumbsup:
 
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