Blowing fuses

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Woodyalan
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Blowing fuses

Post by Woodyalan »

Hi,
Have a question on electrickery. The Minor I am restoring is blowing the ignition fuse every time it is switched on. I found by removing the speedo from its place and leaving it dangling on its wires the fuse would not blow but on replacing the speedo and switching on the fuse would melt immediately. Also the green wire from the fuse box to the wiper motor (via the fuel gauge) would now be live to earth. I thought it might be to do with the connections to the fuel gauge maybe being the wrong way round but swapping them over made no difference. I can get the wiper motor working by disconnecting the fuel gauge but what could be causing the problem?
Thanks for any help
Alan
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geoberni
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Re: Blowing fuses

Post by geoberni »

What year, era?
Is it just connections on the back of the speedo or is it a later model with the Voltage Regulator for the fuel gauge?

There's plenty of connections at the fuse, disconnect them all and try them one by one.
To save on fuses, and potential wiring damage, testing with a meter would be a good option.

If you've never had the car running, or it's been apart for restoration, go through all the wiring, wire by wire, because it sounds as though there is a short to earth on that area of the wiring, possible via the Speedo casing.

I don't understand the remark
Also the green wire from the fuse box to the wiper motor (via the fuel gauge) would now be live to earth.
Green Wires are live when the IGN is on, that's their role in the world.... :-?
Basil the 1955 series II

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Woodyalan
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Re: Blowing fuses

Post by Woodyalan »

Sorry Geoberni
What I meant was the wire is acting as an earth (using a test lamp, it lights the lamp as an earth connection would). The car is 1962 so no voltage regulator on the speedo.
Alan
Woodyalan
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Re: Blowing fuses

Post by Woodyalan »

I tried all the green wires on the fusebox , it was the wire to the wiper that was acting as an earth.
Alan
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geoberni
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Re: Blowing fuses

Post by geoberni »

Alan
disconnect the green wire at the wiper Motor and see what happens.
It could be going to earth through the wiper motor, or there could be a trapped short in the wiring. You appear to be looking in the right place on the circuit to find something.
At least it's easy to get to on a 1000.
Basil the 1955 series II

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