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MG MGB Technical - ignition light

I have a 64 B which I converted to an alternator system. I used a modern Delco alternator with a mid 70's double pulley from a full sized GM car. I have retained the original voltage regulator to this point. This was all done last year. I am now having charging problems with the system. I put in a new NOS regulator and have checked the output of the alternator. It seems that the points in the regulator are not working correctly. When the alternator was first put in I had to adjust the points. I have tried this to no avail and I got stuck coming home last night when the battery ran out of juice and would not run the car . I got a battery pack and came home. Anyone have any ideas on the problem. Thank you very much for any consideration.
Ed Kulick 64B &72 midget
E kulick

You can't run a dynamo control box with an alternator. The original alternators did have a remote regulator but even that was a completely different animal to the dynamo control box. From 1969 MGB alternators used an internal regulator, I would be surprised if mid-70s GM were any different. Internally regulated alternators normally have one or two large output spades which go to the battery cable on the solenoid, and a standard-sized spade to which connects the brown/yellow from the ignition warning light. For an externally regulated alternator you must only use the regulator designed to go with it, no other.
Paul Hunt

Paul, Is there any wiring diagrams that you know of that will show how to rid the car of ther external regulator and let the one on the alternator take over? Thanks for your help. ED
E kulick

Ed, there are schematics of dynamo and alternator systems at http://www.mgb-stuff.org.uk/wn_electricsframe.htm then click on 'Schematics' and 'Dynamo and Alternator' which may help. At its simplest it is a matter of removing the brown and brown/green wires from the original control box and connecting these together, then removing the two brown/yellow wires from the control box and connecting them together if they are not already. These joinings must be secure and carefully insulated to prevent them from coming into contact with anything else. The brown/green goes to the output terminal (or one of them) of the alternator and the brown/yellow to the IND terminal which usually has the smaller of three spades. That will be fine if you have not added lots to the electrical load of the car, if you have you really need an additional heavy gauge brown from the alternator output to the battery post on the solenoid.
Paul Hunt

Paul, Thank you very much for the information, I appreciate the time you have spent helping me.
Ed Kulick
E kulick

:o)
Paul Hunt

This thread was discussed between 29/06/2003 and 03/07/2003

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