Intermittent Charging Problem??? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

SprayPaint · 12-03-2003, 10:48 PM

Hey Guys,

My 1967 C20 has an intermittent charging problem. I start the engine once, and it’s charging. Turn it off and restart, and its not. Retry a few times later, it’s charging again, and so on.

I have replaced the alternator, battery, battery cables and grounding cables as well as continuity checks on the alternator harness. I’ve even run a separate ground wire from the battery to the regulator to make sure it has a good ground. When I install a brand new regulator it won’t charge at all. I put the old regulator back on, and it charges for a while, then not. I’ve heard something about polarizing the regulator but the new one did not come with any instructions on how to do that.

I’m out of ideas and at my wits end with it. Please let me know if anyone has any ideas. The truck is new to me as well as this board. I’ve enjoyed reading so many other great suggestions from you all. My hope is that you can help me on this one.

Thanks!

dinnut · 12-03-2003, 10:51 PM

mine does this too i think except i got a 70 c10

jef5150 · 12-03-2003, 10:58 PM

im assuming you are looking at a "dash gauge" when you say "sometimes its charging,sometimes its not" Maybe the "gauge" is the problem?????..just a thought.... jeff

dinnut · 12-03-2003, 11:04 PM

gauge doesnt work on my mine

**old Rusty C10** · 12-03-2003, 11:06 PM

check the ignition switch is it possible its dirty or somethng and not allowing a circut to complete for the alternator to work? also the regulator may be getting hung up inside ?>

SprayPaint · 12-03-2003, 11:26 PM

It's definitely not charging, drops under 12 volts with lights on with no change on engine rpm. So it's not the guage...

cableguy0 · 12-04-2003, 12:16 AM

what guage are you using. are you using a handheld voltmeter or battery tester if not you need to because none of the ampmeters or voltmeters that are accessory guages are known for there accuracy.

SprayPaint · 12-04-2003, 12:29 AM

I'm using a handheld digital multimeter.

Longhorn Man · 12-04-2003, 12:48 AM

Does the voltage go up as soon as you crack the throttle open?

SprayPaint · 12-04-2003, 01:17 AM

No it does not. I can also tell by the headlights having no change in intensity.

When it's charging, you can tell. The difference is very noticeable.

tom hand · 12-04-2003, 01:32 AM

You probably have some intermediate problem in your wiring. Also you said it charges sometimes with the old regulator but not with the new....a lot of new regulators are not worth a crap right out of the box. My advice would be to by a 1 wire alternator....this would eliminate the external regulator and 90% of the wiring...your problem will go away with this solution...unless your a hardhead....like I am...and refuse to let this beat you...Good Luck

hanssolo · 12-04-2003, 09:55 AM

How old are the connectors? They can get pretty corroded after 20 years. The winter roadsalt always seemed to eat up my regulator connections. I upgraded to a SI 10 this fall and replaced all the connectors. No more flaring headlites.

SprayPaint · 12-04-2003, 01:52 PM

Sounds like there is no obvious trick I've missed. Conversion to an an internal regulated alternator sounds like a good way to go. I've been reading up on it from some other posts, doesn't sound too hard. I'll let you all know how it goes.

12-03-2003, 10:48 PM	#1
SprayPaint Registered User Join Date: Oct 2003 Location: Kingsville, MO Posts: 19	Intermittent Charging Problem??? Hey Guys, My 1967 C20 has an intermittent charging problem. I start the engine once, and it’s charging. Turn it off and restart, and its not. Retry a few times later, it’s charging again, and so on. I have replaced the alternator, battery, battery cables and grounding cables as well as continuity checks on the alternator harness. I’ve even run a separate ground wire from the battery to the regulator to make sure it has a good ground. When I install a brand new regulator it won’t charge at all. I put the old regulator back on, and it charges for a while, then not. I’ve heard something about polarizing the regulator but the new one did not come with any instructions on how to do that. I’m out of ideas and at my wits end with it. Please let me know if anyone has any ideas. The truck is new to me as well as this board. I’ve enjoyed reading so many other great suggestions from you all. My hope is that you can help me on this one. Thanks!

12-03-2003, 10:51 PM	#2
dinnut Registered User Join Date: Apr 2003 Location: missouri city, tx Posts: 4,486	mine does this too i think except i got a 70 c10 __________________ 70 longbed 496/th400/Ford 9"

12-03-2003, 11:04 PM	#4
dinnut Registered User Join Date: Apr 2003 Location: missouri city, tx Posts: 4,486	gauge doesnt work on my mine __________________ 70 longbed 496/th400/Ford 9"

12-03-2003, 11:06 PM	#5
old Rusty C10 Robert Olson Transport Join Date: Oct 2002 Location: recent transplant to NC USA Posts: 20,275	check the ignition switch is it possible its dirty or somethng and not allowing a circut to complete for the alternator to work? also the regulator may be getting hung up inside ?> __________________ Bob 1951 International running on a squarebody chassis "If a man's worth is judged by the people he associates himself with, then i am the richest man in the world knowing some of the fine people of this board" http://67-72chevytrucks.com/vboard/a...t.php?f=25&a=9 (you can review the site rules here!) PM Me for your vehicle/parts hauling needs in the North East US or see my Facebook page Robert Olson Transport Live each day to the fullest.. you never know when fate is going to pull the rug out from under you... I hate cancer!!

12-04-2003, 12:16 AM	#7
cableguy0 Senior Member Join Date: Apr 2000 Location: Delta,Pa Posts: 14,950	what guage are you using. are you using a handheld voltmeter or battery tester if not you need to because none of the ampmeters or voltmeters that are accessory guages are known for there accuracy. __________________ Owner of North Point Car Care in Dundalk Md. We specialize in custom exhaust on both modern and classic vehicles. We are a full service auto shop from classics to modern vehicles. Feel free to contact me with questions. I will give a 10% discount to any board member.

12-03-2003, 10:58 PM	#3
jef5150 Inline 69 Join Date: Apr 2003 Location: valleysprings,california Posts: 1,018	im assuming you are looking at a "dash gauge" when you say "sometimes its charging,sometimes its not" Maybe the "gauge" is the problem?????..just a thought.... jeff

12-03-2003, 11:26 PM	#6
SprayPaint Registered User Join Date: Oct 2003 Location: Kingsville, MO Posts: 19	It's definitely not charging, drops under 12 volts with lights on with no change on engine rpm. So it's not the guage...

12-04-2003, 12:29 AM	#8
SprayPaint Registered User Join Date: Oct 2003 Location: Kingsville, MO Posts: 19	I'm using a handheld digital multimeter.

12-04-2003, 12:48 AM	#9
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	Does the voltage go up as soon as you crack the throttle open?

12-04-2003, 01:17 AM	#10
SprayPaint Registered User Join Date: Oct 2003 Location: Kingsville, MO Posts: 19	No it does not. I can also tell by the headlights having no change in intensity. When it's charging, you can tell. The difference is very noticeable.

12-04-2003, 01:32 AM	#11
tom hand CCRider Join Date: Feb 2000 Location: Olive Branch,MS,USA Posts: 2,232	You probably have some intermediate problem in your wiring. Also you said it charges sometimes with the old regulator but not with the new....a lot of new regulators are not worth a crap right out of the box. My advice would be to by a 1 wire alternator....this would eliminate the external regulator and 90% of the wiring...your problem will go away with this solution...unless your a hardhead....like I am...and refuse to let this beat you...Good Luck __________________ 72 GMC Sierra SWB almost finished---- 84 Softail Olive Branch MS

12-04-2003, 09:55 AM	#12
hanssolo Registered User Join Date: Sep 2001 Location: central Ill. USA Posts: 447	How old are the connectors? They can get pretty corroded after 20 years. The winter roadsalt always seemed to eat up my regulator connections. I upgraded to a SI 10 this fall and replaced all the connectors. No more flaring headlites. __________________ 69 C10 longbed: 357c.i. /TH400/3.73s/AC/ beige primer/saving $ for paint ______________________________

12-04-2003, 01:52 PM	#13
SprayPaint Registered User Join Date: Oct 2003 Location: Kingsville, MO Posts: 19	Sounds like there is no obvious trick I've missed. Conversion to an an internal regulated alternator sounds like a good way to go. I've been reading up on it from some other posts, doesn't sound too hard. I'll let you all know how it goes.



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.