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Electrical issues (Read 1201 times)
Oct 6th, 2016 at 5:11pm

77vette   Offline
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Sioux Falls, S.D

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Hope everyone is doing well.
Took the 77 out last Sunday for the first time this year and ran into a few issues and need some advice.
1st issue - The alt gauge is running on the high side, almost in the red. I think its over charging and this caused the second issue.

2nd issue - While driving through some curves early in the morning the headlights quite working. I am not sure if they recessed or shut off. After getting off the side of the road I pushed in the headlight switch and pulled it back out and they came back on, didn't have any issues on the way back home,that's when I noticed the above issue.

So I am thinking its a bad regulator in the Alternator and the switch going bad.

Thoughts?
 

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Reply #1 - Oct 7th, 2016 at 4:46am

68-73   Offline
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I would disconnect the battery, then take the ALT off. Take both to a good alt shop & have both checked. While the alt is there have them replace the bearings in the alt. I'm thinking that the 77 has an internal regulator, but I'd have to look it up to be sure. Over charging can cause serious problems so get it fixed before you drive it again.
Alan Smiley
 
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Reply #2 - Oct 7th, 2016 at 5:15pm

77vette   Offline
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Sioux Falls, S.D

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Alan, I think you are correct, I believe it does have an internal regulator.
Took them both in today, the auto shop said both are good. The counter person had to get someone else to test it since at first he could not get a reading. May be time for a second opinion.
Ron
« Last Edit: Oct 7th, 2016 at 5:15pm by 77vette »  

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Reply #3 - Oct 8th, 2016 at 5:28am

68-73   Offline
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I would check the voltage at the alt with the engine at around 2K with no load. It should be pretty close to 14.1-14.4v. Them check it with a load ..lights on etc. Do the same at idle..the voltage will probably be a bit lower around 13.8v or so.It should be just about the same maybe a little lower but not higher.  Remember all auto shops are not created equally. Also with everything off check the voltage at the battery & the alt they should be almost the same maybe a .1 off & read about 12.2 v or pretty close. What you're looking for is consistent readings & no high or low readings.
Let us know what you find. If you find the alt bad you can go to a 1 wire 100amp pretty reasonable.
Alan Smiley
 
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Reply #4 - Oct 11th, 2016 at 4:23am

77vette   Offline
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Sioux Falls, S.D

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Alan,
Quick update. Took the alternator and battery to a different store to have it retested on Sunday, the results varied from the first. The alternator put on 14.6 and the battery tested good but needed to be recharged. Came home and put the battery on the charger so everything was good before I started getting the readings that you suggested. The battery has been on the charger for a total of 10 hours and will not completely charge, has been on the first mark of the charger gauge for over 5 hours. Starting to think the battery will not fully charge.
« Last Edit: Oct 11th, 2016 at 4:24am by 77vette »  

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Reply #5 - Oct 11th, 2016 at 4:47am

68-73   Offline
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It can take 1 or 2 days to charge a dead battery sometimes. Put it on a low amp charge 2-4 amp. A dead or weak battery will cause a alt to go nuts. After all is well get a battery tender & use it. I have one on all my classics & the batteries last forever.
Alan Smiley
 
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Reply #6 - Oct 11th, 2016 at 4:33pm

77vette   Offline
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Sioux Falls, S.D

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Alan,
Thanks I will keep trying to charge it for a while longer. The wife and I were talking about getting a battery tender, guess its time to stop talking  Smiley

Ron
 

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Reply #7 - Oct 12th, 2016 at 4:14am

68-73   Offline
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This is the charger I use & have for many years. I have a few older models too. They do the job & will charge a batteryquite well too. They actually keep the battery at a full charge all the time so they last twice as long. The initial investment pays off in the long run. I keep them on all the classics all the time. Hook  the positive cable to the + on the ALT & the ground to any place in the engine I use the break line.
Alan Smiley

https://www.amazon.com/Schumacher-SC-600A-CA-SpeedCharge-Frequency-Battery/dp/B0...
 
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Reply #8 - Oct 13th, 2016 at 4:43pm

77vette   Offline
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Sioux Falls, S.D

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Thanks Alan,
I went and purchased a new battery and a battery tender last night. Had the old battery on the charger at work, wanted to make sure it wasn't my charge, would charge to 100% but the CCA would not come up past 273 and if you shut it off for the night it will drop to 75%. Started it back up and did the same thing the next day. They did prorate the battery so it took some off the final price.
Alt gauge is back where it should be, now to enjoy it for the next few days before the  snow starts to fly.
Ron
 

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