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polarity swap

Posted: Thu Nov 18, 2010 9:46 pm
by rustbucket
i have a 66 2dr saloon that has been totaly striped back to the bare shell. for the rebuild i wish to run the engine with an alternator. There is not a wire left on the car, the loom was removed and ditched because it was complete trash and looked a mess. i know that you can buy looms for use with an alternator. while i was striping down the heater box for powdercoating a thought came to mind. if you swap from + to - earth will the fan suck instead of blow?. then i thought what about all the gubbings in the speedo? now electrics to me are a mystical dark art and belong in the kingdom of arthur and merlin. is it that easy to just swap round the battery terminals? don't forget there will be no wiring for the voltage regulator on a loom for an alternator. will there be something else i have to do? give me a spanner and a bearing any day. :(

Re: polarity swap

Posted: Thu Nov 18, 2010 10:29 pm
by bmcecosse
Just fit new points in the dizzy and the fuel pump. Nothing will run the wrong direction.

Re: polarity swap

Posted: Thu Nov 18, 2010 10:29 pm
by mike.perry
Order a new loom for an alternator and include any extras you may have, reversing lights, rear fog lights, etc so that it is all included. It is recommended that you swap the connections over on the coil and clean the petrol pump contacts but apart from that everything should be ok, your starter motor will not run backwards. If you have electric washers you may have to swap the connections but as you have no wires to start with you have a 50/50 chance of getting it right. You can feel if the air is flowing the correct way through the heater, if not swap the connections.