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Discussion Starter #1
Hello,

I am having some pretty major alternator issues at the moment and have a technical question which I think has probably never been asked before but here goes.
The background is the alternator stopped working with no warning. I tested everything with details I found on this forum (thanks) and found it was totally broken. I ordered a reconditioned one from a major parts supplier here in the UK and after 4 weeks it turned up and was the wrong model so I ordered another one from a small alternator rebuilders and this one was the right model but the shaft was seized. I then did some research and went back to the original broken unit and found that it had a shorted diode in the diode pack, I ordered an aftermarket diode pack from Poland which has arrived today.

So here is the question:
The original diode pack configured the alternator in a delta formation however the new diode pack is in a star(wye) formation. So would you just fit it and see what happens or go back and try to find a delta sytle pack?

Sorry for the long post but I am really at a loss with this issue. I didn't mind spending £350 on a reconditioned unit but £1,200 for a new one is a bit steep for me. Thanks for reading and ideas would be great as I have been without a car fo 10 weeks, not that there has been much to do anyway.

Thanks,
Alan.
 

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01 Carbon/Silverstone Exhaust: Jedders-HJS high flow cats-resonator delete-Xpipe-Eisenman cans
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Personally I would try to make it the same as before. Changing configuration will cause changes in line vs. phase currents and voltage. The VR does some complex things as indicated in TIS. Plus the hassle of getting the alt in and out of the car, I wouldn't want to chance having to pull it again.
 

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Discussion Starter #3
Thanks for the reply. I am leaning that way, from what I have read the star setup seems to give a higher voltage and less current which is probably not what the car needs. It never had a problem making 13.8 volts at tick over on the old rectifier. I can not seem to find anywhere in the UK that can supply an alternator for the car.
 

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01 Carbon/Silverstone Exhaust: Jedders-HJS high flow cats-resonator delete-Xpipe-Eisenman cans
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Maybe @sreten can chime in I think he did an alt rebuild and he's in Europe.
 

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01 Carbon/Silverstone Exhaust: Jedders-HJS high flow cats-resonator delete-Xpipe-Eisenman cans
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Eh looks like he just changed the VR and bearings. Can you post pictures of the two different diode packs?
 

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Discussion Starter #7
I have cut the old one in half to test the diodes individually. The two packs are identical but when I tested the posts that connect to the windings I found they wire the windings together differently. Hope that makes sense!!
 

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Discussion Starter #8
I found a reconditioned complete alternator on ebay that I am going to try out. Thanks for your replies, I did think changing the setup was a bad idea but it is good to get some input from someone else.
 

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