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Electrical problem

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Lin

Lin

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I need a little help getting started with solving this problem:

I am installing a new alternator in my son's Bugeye. We had a Lucas alternator in it before. I have just installed a mitsubishi unit. Had to do a little bracket work and the usual fitting, but in the end I was pleased with the effort.

I had a three prong plug on the Lucas alt. Big spade brown wire from the battery, two little ones - one for the brown/yellow wire that I think is the indicator warning light to the speedo, through the ignition I believe. I forget what the other small wire is, sourced from the no longer used voltage regulator.

On the mitsubishi alternator, the big brown wire (big spade connector) from the battery connects to a scew terminal on the back of the unit. The other two small wires from the Lucas plug were spliced into the Mitsubishi two prong plastic plug and plugged into the back of the alternator.

I then checked my battery -fully charged, and turned on the ignition. Got nothing, No fuel pump ticking, no fuel gauge jumping into action. I have spark to the alternator through the brown wire from the battery. The starter works fine. But, nothing at the ignition switch. No obvious lose wires and everything worked before the alternator change over. No blown fuses.

Can anyone help me with a troubleshooting plan of attack? Probably something silly or stupid that I overlooked.

Thanks.

Lin
1960 BT7 in restoration
1959 Bugeye
 
Hello Lin,

the usual feed to the ignition is a heavy brown wire taken from the starter solenoid (Where the battery and alternator cable also connects). Did you disturb any of those connections?

What do you mean by "I have spark to the alternator"?
If you test for power by shorting to earth you can cause all sorts of damage to electronic components and to the battery.

Alec
 
Hi Lin,
I’m not familiar with the Bugeye, but here goes. I installed a Delco alt in my BJ8. The wire that charges the battery (output) has two connections on the alternator. One of those connections is in the two-prong plug. The other wire is the brown/ yellow wire. The original brown/green wire I cut out completely. Here is the only handy photo I have. Without knowing how the Mitsubishi is supposed to be hooked up, it’s kind of a crapshoot.
211172-alternator.jpg
 
Greg,
If I understand, you say that there are two connections: "The wire that charges the battery (output) has two connections on the alternator. One of those connections is in the two-prong plug. The other wire is the brown/ yellow wire."

But your image shows the brown/yellow wire in the two-prong plug? Huh?

Lin
 
Hi Lin,
Sorry, I could have been clearer. The red wire in the photo comes out of the 2-prong plug and attaches to a post on the back of the alternator. Another wire on the same post goes to the battery side of the starter solenoid. The brown/yellow wire goes to voltage regulator, then on to the charging light in the tach. The Delco has an internal regulator so my original regulator on the firewall is just a distribution box now.
 
If I remember, the 10SI Delco shown above has a feedback wire on terminal "2" to the main output stud. I think this is a feedback connection for the "sense" circuit. I'm not familiar with what's on the Mitsubishi.
 
Thanks to everyone for the help. I think I have it figured out now. I have to go out of town for a few days. I will report back next week with an update!
Lin

1960 BT7 in restoration
1959 Bugeye
 
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