voltage regulator issue?
Thread Starter
|
Senior User
Joined: May 2003
Posts: 160
Likes: 0
From: Benbrook, Texas
voltage regulator issue?
Happy Thanksgiving,
After lots of recent trouble-free service, my '78 F-150 has decided to ask for some TLC this month. A new P/B booster (two weeks ago) and two new Goodyears (yesterday) wasn't enough, today it didn't even turn over! Here in DFW, it just got cold so I assumed it was the battery. It's a 72 month warranty battery and it's 41 months old, so it's certainly something I'm going to have tested tomorrow.
The weird thing is that when I jump started it today, I put a voltmeter on the battery terminals and it read 15.5 volts (at 750 rpm idle, and choking at 2000 rpm). I once had a diesel Mercedes that had a voltage regulator fry and the meter read 18 volts and wouldn't charge the battery at all. What are the symptoms of a dead voltage regulator? Is 15.5 volts way too high from the alternator? A dead cell seems more likely, any thoughts?
Thanks in advance and enjoy the turkey!
Bob
After lots of recent trouble-free service, my '78 F-150 has decided to ask for some TLC this month. A new P/B booster (two weeks ago) and two new Goodyears (yesterday) wasn't enough, today it didn't even turn over! Here in DFW, it just got cold so I assumed it was the battery. It's a 72 month warranty battery and it's 41 months old, so it's certainly something I'm going to have tested tomorrow.
The weird thing is that when I jump started it today, I put a voltmeter on the battery terminals and it read 15.5 volts (at 750 rpm idle, and choking at 2000 rpm). I once had a diesel Mercedes that had a voltage regulator fry and the meter read 18 volts and wouldn't charge the battery at all. What are the symptoms of a dead voltage regulator? Is 15.5 volts way too high from the alternator? A dead cell seems more likely, any thoughts?
Thanks in advance and enjoy the turkey!
Bob
Laughing Gas
Joined: Feb 2007
Posts: 821
Likes: 0
From: hohenwald, tn
that is charging a bit high. usually around 14 and a half volts is good. most likely the regulator is getting lazy and just about working. if you have an autozone or advance auto in your area start it bring it to them and they use a good tester to pinpoint the exact problem for you.
Thread Starter
|
Senior User
Joined: May 2003
Posts: 160
Likes: 0
From: Benbrook, Texas
Cheers, Rusty. I was going to toss the battery in my other truck (that still starts) and have it checked, but if they can check the V/R, I'll jump the Ford and take it to the local AutoZone tomorrow.
Regards, Bob
Regards, Bob
Thread Starter
|
Senior User
Joined: May 2003
Posts: 160
Likes: 0
From: Benbrook, Texas
Will do, I was a little worried about turning it off and being stranded and at the mercy of the AutoZone guys' booster battery or troubleshooting to get home!
I'll let you know what I find.
Thanks!
Bob
I'll let you know what I find.
Thanks!
Bob
Senior User
Joined: Aug 2004
Posts: 285
Likes: 0
From: Terre Haute, Indiana
I remember when I had problems with mine and it seemed to only happen when hot outside, I took a hairdryer to mine with the truck running one early morning and after a short time it quit working, threw it away and installed a new one.
Problem solved.
Problem solved.
Thread Starter
|
Senior User
Joined: May 2003
Posts: 160
Likes: 0
From: Benbrook, Texas
This morning I had the battery tested, I was going to walk around the store but the tester beeped before I could turn around, definitely toast. I thought it might have been because of the V/R cooking it, but Autozone said they couldn't test it...so I bought another one just in case. I reinstalled the old V/R (AZ sells Wells, not something I was looking forward to) and new battery and fired it up. The voltmeter says output is right at 14.4 volts again. I don't know why it was up to 15.5+ with the bad battery last night. I'll check output from time to time to see if there's not an intermittant V/R issue.
Thanks to all that helped, you guys are invaluable!
Bob
Thanks to all that helped, you guys are invaluable!
Bob
