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the millionth alternator question been searching for days.
Ok so I'm sure my 67 cutlass was working with just the 1 wire going to the horn relay but now I'm not getting a charge. There is a chance it never worked I have always had other issues. In the pic is the plug on the back and the 2 wires on the voltage regulator that it looks like a different alternator was put in. The car is new to me so I have no clue how it's wired. Can someone please walk me through this alternator and the new one failed voltage regulator test at oriellys. Anyone that can help explain this to me and if I need to hook up more wires or buy another alternator.
The alternator in the car is a later internal regulator unit, apparently a 12SI. The plug in your first photo is from the original 10DN external regulator alternator. The third photo is the old external regulator. The old plug and old regulator should be disconnected from the electrical system.
Ok so I followed the diagram I found on here putting the red to white then brown to blue then hooking it up to this alternator my guess is the alternator went bad. The gen light on my dash doesn't work but non of the dash lights work besides the high beam light. My question is what alternator can I buy at the parts store for this car to convert it back to a 3 wire since it seems no one likes the 1 wire set up. Like what year or model should I look for. It's a 67 cutlass with a 425 electric fans and a little stereo system in it.
Ok so I followed the diagram I found on here putting the red to white then brown to blue then hooking it up to this alternator my guess is the alternator went bad. The gen light on my dash doesn't work but non of the dash lights work besides the high beam light. My question is what alternator can I buy at the parts store for this car to convert it back to a 3 wire since it seems no one likes the 1 wire set up. Like what year or model should I look for. It's a 67 cutlass with a 425 electric fans and a little stereo system in it.
Your second photo shows that the 12SI you have IS a three wire connector. There are two in that plastic connector that plugs into the case and the third is the wire that goes to the threaded BATT terminal on the back of the alternator. The fact that none of your dash lights work is likely unrelated to the alternator wiring, and if there is no power to the instruments, the GEN light won't work even if the alternator is good. If you turn the key to RUN without starting the engine, does the GEN light come on? If not, the problem may or may not be the alternator.
Ok so wait my alternator is a three wire and I should hook it up without bypassing the voltage regulator? And this car has been an absolute nightmare with everything I'm sure the dash lights don't work cuz they are not wired up right. I'm just trying to figure out how to get the alternator to charge or what I need to buy to get it to work.
This is the diagram I used to try and get this thing to charge. I'm guessing it's the wrong one for my alternator. Going out to figure the gen light issue right now will get that working
This is the diagram I used to try and get this thing to charge. I'm guessing it's the wrong one for my alternator. Going out to figure the gen light issue right now will get that working
That diagram is intended for converting an unmolested external regulator system to internal. Unfortunately, whoever converted your car did not follow this, so don't waste your time trying to understand it. Simply look at the wires on your car. The red wire from the #2 terminal on the new alternator needs to run to the threaded post on the horn relay. The heavy wire from the threaded BATT terminal on the alternator also needs to run to the horn relay. The #1 wire from the alternator needs to connect to the brown wire that feeds the GEN light. That's all you need. Of course, this ASSUMES that the wiring under the dash is correct. It sounds like it is not, and you need to figure that out first. I would also suggest that you simply take your alternator to an auto part store like Advance or AutoZone and have them test it for free.
Found some wiring under the dash that I don't like so now the whole dash is coming out and I'm going through all the wiring this car had been a wiring nightmare but at least I know when I'm done it will be done right and I won't have anymore electrical issues
Had them test it and it failed the voltage regulator test but so did the new one. I'm assuming that the gen light needs to work for the resistance for the alternator to ignite? Everyone laughed at me for putting a fire extinguisher in the car the first day I got it lol. Glad it was in there just need to sort this mess out under the dash. Probably take the alternator in while the car is down just incase. But thank you guys for your help.
Perhaps the harnesses can be repaired, but just so you know, Lectric Limited, and American Auto Wire make new reproduction harnesses for 67's. I have a main dash, and ignition harness
from Lectric Limited in my 67. They are very nice, all the factory plugs and color codes. You just have to send your original 67 fuse box because they dont repo those, they use yours.
Ok guys seems to be working just fine with the 1 wire off the post hooked up no plug I only have seen a little over 13 on my multi meter but I think I've dropped it to many times not sure if it's still good. But it's firing right up everytime no issue even after warmed up. All I've done is fixed the burnt wiring I found probably from people twisting the key trying to tighten that to the dash. Put a thicker wire from the alternator and added a ground. I think I'm gonna add a few more grounds to the car.
March 13th, 2019, 09:34 AM
