One wire alternator problem
Thread Starter
Pro
Joined: Jun 2007
Posts: 688
Likes: 1
From: Stevens Point WI
One wire alternator problem
I have a brand new chrome one wire alternator on my 69 that does not seem to work, but I want to try every test possible to make sure its bad before I pull it off the car.
Battery is at 12 volts
Reading at alternator with car off 12volts
Car running 11.6 and falling tested at alternator
Add load of headlights, radio, spal fans, and heater blower, gave me a reading of 10.4 volts and raising the rpms past 2000 changed nothing
I also ran additional ground wire from the alternator case to ground which changed nothing
My gauge in the car is changed to a voltmeter and has never read above 12 volts which is what caught my attention to this matter as I have used one wire setups before and always remember them showing like 14 volts.
Are there anymore on car test's I can perform to make sure the alternator is faulty?
Battery is at 12 volts
Reading at alternator with car off 12volts
Car running 11.6 and falling tested at alternator
Add load of headlights, radio, spal fans, and heater blower, gave me a reading of 10.4 volts and raising the rpms past 2000 changed nothing
I also ran additional ground wire from the alternator case to ground which changed nothing
My gauge in the car is changed to a voltmeter and has never read above 12 volts which is what caught my attention to this matter as I have used one wire setups before and always remember them showing like 14 volts.
Are there anymore on car test's I can perform to make sure the alternator is faulty?
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I'm pretty sure the alternator is bad but you can take it by an Autozone or Oreillys and they can load test it for you. Sounds like a bad alternator. Now, you can actually rebuild the one you have if you want to and build it to a 3 wire...or you can just buy whatever style you want. I like putting on newer style CS130s. You get more power and they are more reliable.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Take that one wire POS off and put the 3 wire back on it, there are a lot of very good reasons GM and everyone quit using the 1 wire system 4 decdes ago.
You have to hunt but can get the 3 wire in chrome too.
You have to hunt but can get the 3 wire in chrome too.
Drifting
Joined: Apr 2008
Posts: 1,540
Likes: 51
From: Lexington Park Maryland
What's wrong with the one wire altenators ?? I've had one on my Corvette for 15+ years and my racecar for about 12 and haven't had any issues.
Safety Car
Joined: Oct 2007
Posts: 3,729
Likes: 267
From: Austin Texas
Corvette of the Year Winner 2017
2016 C3 of Year Finalist
1 or 3 wire Alternator ??
the great Debate, do some research,
basicaly the 1 wire was designed for a quick and easy install.
the 3 wire gives you 2 basic benifits,
1. your alternator lite/ gauge still works
2. remote voltage sensing, provides better voltage control of your complete system.
69VETT
basicaly the 1 wire was designed for a quick and easy install.
the 3 wire gives you 2 basic benifits,
1. your alternator lite/ gauge still works
2. remote voltage sensing, provides better voltage control of your complete system.
69VETT
Thread Starter
Pro
Joined: Jun 2007
Posts: 688
Likes: 1
From: Stevens Point WI
going to try to hook it up to only a battery and see what happens but I think it was dead in the box when I got it.
I will see if carquest has a 3 wire chrome one
I have used 1 wire alternators in boats for years without a problem, and thats tied to a 1000hp blower motor too
If I end up with a 1 wire or any other one for that matter its getting tested before it goes into the car, cause its going to take some time to get that off the BB stuffed in the vette
I will see if carquest has a 3 wire chrome one
I have used 1 wire alternators in boats for years without a problem, and thats tied to a 1000hp blower motor too
If I end up with a 1 wire or any other one for that matter its getting tested before it goes into the car, cause its going to take some time to get that off the BB stuffed in the vette
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Racer
Joined: Jan 2008
Posts: 379
Likes: 10
From: N'Awlins
Don't buy from Auto Zone, Pep Boys... find out where the truckers and heavy equip guys bring their starters and alternators for rebuild. Those shops completely rebuild/change everything. Their livelihood depends on quality! You'll never go back to the other guys.
Thread Starter
Pro
Joined: Jun 2007
Posts: 688
Likes: 1
From: Stevens Point WI
I figured since he bought the same exact alternator last summer for his 57 nomad and it worked great that I would give it a try.
Guess I should not buy a lottery ticket anytime soon huh
Racer
Joined: Jan 2008
Posts: 379
Likes: 10
From: N'Awlins
Sorry, Fonz69, wasn't trying to insult you or your dad. I was just passing along personal experience as I own both classic cars and heavy equipment. And have had to return starters and alternators bought at discount stores because of poor quality. Never had problems with the specialty shops. Hope your alternator last you a lifetime, good luck.
