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MGB mystery wire

PSSST! Mick! Already gone there. ;)
 
Also, note that the second fuse down from the top of the block has no connection on the left side.
That fuse is bussed with the one above it to power front and rear parking lamp circuits, Tom.
 
Stupid question: Do the reverse lights work? Altho that wire doesn't appear long enough to go all the way to the reverse switch.
 
Frustrating to be a continent away from the car! That wire is "native" to the thing, heavier and shielded. Meant to be in a more severe enviorn. I've not had occasion to look under-bonnet of a later B for most of a decade now but that wire looks familiar, just can't place it. And no car of the same years around to put a Mk-I eyeball on.

And an aside, the piece of hose wedging the connector of the Otter switch in place suggests the connector may be why the fans don't come on: Damaged or loose contacts in it?
 
Your right on both accounts. According to the wiring diagram, and the fact I have no reverse lights, or heater operation, I have found a junction on the schematic that suggest that my wire might be the power source for that junction. I now need to find the junction and test for power with a test light and see if there is any power there. I should see the other end of the terminal connection where ever it may be.

Regarding the otter switch, I think your right. I believe the fan not working to be a separate issue, and most likely the switch is no good. I will check that out later. thanks for the suggestions, and I will update once I have a development.
 
Possibly the induction heater for the carb....

That's it! Thanks, Joe! I'd completely forgotten about that poxy thing.

Svc, that's why the heavier gauge wire and sheath. The heater is between carb and manifold. What carb is on your car?
 
We have a winner!!! That was exactly it. The carb is a Zenith. I also figured out the reverse light issue, lol. Bad connection at the tranny and one burnt out bulb.
 
We have a winner!!! That was exactly it. The carb is a Zenith. I also figured out the reverse light issue, lol. Bad connection at the tranny and one burnt out bulb.
Sorry it took so long to suss it! Joe came into it with the real answer.
Thank you DrEntropy, Joe, NutmegCT and Mickey for the assistance. I really appreciate it.
Again, Joe saved th' day. (y)
 
I've been playing the "where does this go" game for a couple weekends now - I have 1970 stuff going into a 1973 body (with seemingly a varient of the 1973 wiring looms). The PDFs of the wiring diagrams are of great help. I know I will have to add some additional wires to go to things which the 1973 body did not originally have (such as the electric oil pressure sender/gauge and the transmission overdrive), and there are some bits or wiring which I will just have to disconnect and wrap up out of the way (the seat weight and belt switches for example, since my seats/belts don't have the corresponding microswitches and connectors). Being able to look back to the 1970 diagrams is wonderful because I can see where the things I need to add should be tied in, and what color wires they should be. I won't be able to wrap them into the original looms but I can at least connect them to the correct places and use the proper colors.
 
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