car runs without keys, upgraded alternator

[vintage_car]

I know that you can put a diode inline with an upgraded alternator that lets the car continue to run. I was using a 4001 I think? Problem is I also remember it burning up the diode, so is there another fix? Can I replace the internal bosch regulator on the alternator with a different kind to allow the car to turn off properly?

[Jaycen_PNW2002]

Start car pull out key go into house get whatever it was that I forgot.

[ClayW]

I know that you can put a diode inline with an upgraded alternator that lets the car continue to run. I was using a 4001 I think? Problem is I also remember it burning up the diode, so is there another fix? Can I replace the internal bosch regulator on the alternator with a different kind to allow the car to turn off properly?

Make sure that the diode is facing toward the alternator.

http://www.bmw2002faq.com/component/option,com_forum/Itemid,57/page,viewtopic/t,339174/highlight,alternator/

[vintage_car]

it does, and does work for awhile, but burns out.

[vintage_car]

1n4004 was the diode... since I recall mine burning out from time to time, is there a larger one that is still safe for the car?

[ClayW]

Not sure where I got mine, but it's about as big around as a pencil. It's been working for years.

[vintage_car]

are there any numbers on it that you could read off so that I might be able to search for one?

[Tommy]

1N4007 is same but bigger. Still not sure if it's enough. There's million of choices e.g. BY255 is considerably larger. You could go to electronic store and just ask for larger diode.

Tommy

[vintage_car]

A larger diode will not affect anything correct? If the 1n4004 is a safe one, i will just place it in an area that is accessible for replacement

[Tommy]

Any regular diode should work there without making difference. It's just about how much current they can lead without heating too much. This is rough interpretation, I know, but correct enough in this application.

Tommy

[Tommy]

BTW, are you sure about your connection? I'm just throwing basics about diodes without knowing what you're actually doing :-)

Tommy

[brianstj]

I just got my DCOEs installed, and the first time I fired it up this happened to me. The only thing I can figure that happened is that I disconnected the wire powering the old electric choke on the 38/38, and I think this circuit may also be powering my MSD box. The choke may have been providing enough load on the circuit to let the car shut off? Anyhow, the MSD instructions provide a schematic and a diode to use if this happens, so I am going to give that a try.