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MGB What is this in a 1977 MGB?

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Alfletch

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There is a retangular box in the engine compartment, about 3 inches forward of the fuse box, that has two wires going to its two terminals, one green wire and the other black.
What is this box?
There is another bigger and squarer box in close proximity to the retungular box.
Al
 
I do have a JPEG picture but I don't know how to upload it.
Let's try this and see.
 
Adding pictures is now a little tricky.

When you post you now need to click on the "File Manager" in the "Post Options" box at the bottom of the entry form (above the "submit" and "Preview Post" buttons).

This then brings up a box that lets your browse for your pictures and select multiple ones, but you then need to "Add" them to your post ofr it to be effective.

Hope this helps....
 
The "File Manager" will NOT show up in the "Quick Reply" frame. Use the "Reply" button in the previous post to access the Manager.
 
Here is the picture using the steps in the previous reply.
Thanks.
 

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Not part of the original wiring!

However, do those wires run to the distributor & coil?
 
Not knowing where the wires go, But, I'd say it's a relay that someone added for the front lights. It definitely looks like a GM relay what ever the case.
 
A "bus" of some sort. Finding where it originates (voltage-wise) and where it terminates are the two things to determine first. It may be an innocuous device like the horns, or something as important as the ignition. Physically trace the two wires and let us know where they go (which devices where they terminate).
 
Some kind of circuit breaker, or flasher module. More likley circuit breaker. Not enough wires to be a relay.
Most likley for some add-on circuit, like a radio, or fog lights, or something like that (Pretty much what everyone else has said)
Follow Docs prescription, and trace out the wires.
 
That is a correct circuit breaker for the cooling fans. I did not think is was used until later cars , though. The early electric fan cars had a line fuse. It is not in the original location either. It should have a green wire on one side and a white with brown trace on the other. Factory part # BLM 601018 or Moss # 131-545.

Alan T
 
The fans on my 1978 MGB run into a relay forward of the ignition relay.
 
That is fine but a relay does not protect the circuit. The car started life with either a fuse or a circuit breaker dedicated to the cooling fans.

Alan T
 
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