Feeling kinda stupid at this point. I have a new to me 73 Dodge Dart Sport. The charging system never worked. The dash wiring was a mess so I replaced it with a donor harness. I have a wiring diagram (colors are not always right but it helps). I have cleaned the bulkhead connectors, check and made a dedicated ground for the VR. Less than 1 ohm from the VR to the engine. I have checked for shorts to ground, no issue found. I have ohmed out the wiring from the VR to the alt., all ok. I have battery voltage (blue) to the VR and the alt. I have less than .1 of a volt Key on at the alt (blue) and battery. I had the alt checked, it was NG. Replaced with reman. Now its putting out 20 volts. Yea, way to hot I know. It is putting out this voltage with the VR disconnected. I removed the green wire from the alt. Still putting out 20 volts at the battery and the back of the alt. I have been reading threads all night. I may be wrong but it seems like there may be a short in the reman alt. Yes, I have seem the one wire options in the threads. ANY help would be great. I went from no charge to holy 20 volts...
BAD (REMAN) ALTERNATOR? OVERCHARGING
- Thread starter spd691
- Start date
-
67Dart273
Well-Known Member
The VERY first thing you need to do, and THIS IS a common problem with rebuilts:
Disconnect both field wires, take your ohmeter set on low resistance, and measure from the alternator case to either of the two field connectors on the alternator. They should both be OPEN, AKA "infinity." Usually the problem is that one brush is INCORRECTLY grounded, either A: wrong or missing parts in one brush holder, or B: Rebuilder PURposely grounded one to "turn it into" a single wire field for 69/ earlier cars
Disconnect both field wires, take your ohmeter set on low resistance, and measure from the alternator case to either of the two field connectors on the alternator. They should both be OPEN, AKA "infinity." Usually the problem is that one brush is INCORRECTLY grounded, either A: wrong or missing parts in one brush holder, or B: Rebuilder PURposely grounded one to "turn it into" a single wire field for 69/ earlier cars
Okay. What are the odds? After coming out this morning and checking field terminals to case and finding that ok. I was checking voltage at the alternator again with out the car running. Measuring 20 volts at the terminal. This is when I figured out the DVOM I was using was junk. I went out and bought another one. Connected the alt. back up. No charge. Grounded the green terminal at the VR. Viola charging. Replaced the VR and all is well. Bad DVOM, bad alt., bad VR. WTH. Thanks for your time 67Dart273.
-
