Anyone had trouble with... - The 1947 - Present Chevrolet & GMC Truck Message Board Network

red71cheyenne · 12-27-2002, 02:43 PM

Thier one wire alternator? Mine doesn't want to maintain voltage very well. Got a new stereo for my B-day and if I'm running all the accessories and the fans kick on, the radio shuts itself off. Must be the regulator. Anyone had this problem and found a way around it? Thanks, Jeff.

jhow66 · 12-27-2002, 03:59 PM

What amp alt. are you using?

red71cheyenne · 12-27-2002, 04:05 PM

Its a 100 amp, but when I had it rebuilt, the guy said it only actually put out like 78 amps.

jhow66 · 12-27-2002, 04:28 PM

78 amps likely is not enough for what you are using. If you have a 100 amp alt. it should put out that much. Must be something wrong with it (regulator?) if it is not. Have it checked with it on truck to see how many amps it is putting out with all your acc. on. This should tell you where to go.

red71cheyenne · 12-27-2002, 04:39 PM

When the guy rebuilt it, he said that almost all of them are mis-advertised. He said it could be brought up to put out 100, but that would require a different stator. I just don't understand why it wouldn't keep it up at 78 amps. Thats running the lights, heater, stereo. Then like I said, if the fans kick on, the lights dim and the stereo shuts off. Would changing it back to a regulator keep it better? Or is the regulator in the alternator sufficient? Thanks, Jeff.

jhow66 · 12-27-2002, 04:47 PM

Internal reg. are all right. The guy was shooting a line to get you to spend some more $'s. 100 amp alt=100amps if alt. is right. Had a 37 amp on my 56 Bel-Air--when using all acc. and rad. fan engine would start to miss and then die--turn off fan would run again. Had it upgraded to 63 amp--it puts out 63 amps. Works with everything on now.

red71cheyenne · 12-27-2002, 04:55 PM

How do I know how much I actually need? Like you said, check it with all accessories running? I have an ammeter, but don't know if it will handle 100amps. It also won't run at less than like 1000 rpm either. When I start it up in the morning, I have to rev the engine to get it to start charging. You know what I mean?

jhow66 · 12-27-2002, 05:03 PM

100 amps should be fine. amp gauge will be fine also as it never shows that much. 1 wire alts. are not self exciting hence you have to rev engine to get them started. Once they are charging they will charge at idle until engine is cut off.

red71cheyenne · 12-27-2002, 05:05 PM

Thanks for the help. When I get it home today, I'll hook up the ammeter and see how much I'm pulling. Jeff.

72K10 · 12-27-2002, 06:39 PM

Stock without air for our pickups is 43 amps, if I recall correctly, and with air it's 62 or so. 78 ought to be enough to handle a regular load with stereo.

mikep · 12-27-2002, 08:55 PM

Even 78 amps is a LOT of current. Unless youv'e got a big amp pushing oversized speakers and a pretty healthy subwoofer theres no way you should be getting close to 78 amps.

Ive got an oversized moroso racing pully on my 135 amp one wire and I have to rev it up to 2000 or so to get it started but once its charging I never have a problem. Thats even with the AC fan motor , halogen lights and stereo at full volume. I cantr imagine that you'd be pulling more than 40 amps at any given time unless youve got something weird going on or somethings not wired right.

Oh wait a minute. The fans kick in? Are you running dual electric fans? If so you probably dont want to run them through the wiring system. A relay directly to the battery ( circuit breaker protected of course ) would be the way to go with a pair of hi current drawing cooling fans if you dont have it set up that way already.

12-27-2002, 02:43 PM	#1
red71cheyenne Back in the sticks Join Date: Jan 2001 Location: Fordland, MO Posts: 3,188	Anyone had trouble with... Thier one wire alternator? Mine doesn't want to maintain voltage very well. Got a new stereo for my B-day and if I'm running all the accessories and the fans kick on, the radio shuts itself off. Must be the regulator. Anyone had this problem and found a way around it? Thanks, Jeff. __________________ 1971 Cheyenne C-10 w/700R4 and Tuned Port Injection 1969 K5 Blazer w/Tuned Port 2010 2SS/RS Flaming Orange Camaro 2011 K1500 Suburban 2014 K1500 Pickup 2008 Nissan Altima? The wifes' hoopty

12-27-2002, 03:59 PM	#2
jhow66 Registered User Join Date: Jun 2002 Location: Knoxville Tenn. Posts: 3,058	What amp alt. are you using? __________________ 56 Chevy Bel-Air 2dr. HT (purchased new) 71 Chevy Cheyenne SWB PU (502HO) 65 GMC short bed step--work in progress and my gofer

12-27-2002, 04:05 PM	#3
red71cheyenne Back in the sticks Join Date: Jan 2001 Location: Fordland, MO Posts: 3,188	Its a 100 amp, but when I had it rebuilt, the guy said it only actually put out like 78 amps. __________________ 1971 Cheyenne C-10 w/700R4 and Tuned Port Injection 1969 K5 Blazer w/Tuned Port 2010 2SS/RS Flaming Orange Camaro 2011 K1500 Suburban 2014 K1500 Pickup 2008 Nissan Altima? The wifes' hoopty

12-27-2002, 04:28 PM	#4
jhow66 Registered User Join Date: Jun 2002 Location: Knoxville Tenn. Posts: 3,058	78 amps likely is not enough for what you are using. If you have a 100 amp alt. it should put out that much. Must be something wrong with it (regulator?) if it is not. Have it checked with it on truck to see how many amps it is putting out with all your acc. on. This should tell you where to go. __________________ 56 Chevy Bel-Air 2dr. HT (purchased new) 71 Chevy Cheyenne SWB PU (502HO) 65 GMC short bed step--work in progress and my gofer

12-27-2002, 04:39 PM	#5
red71cheyenne Back in the sticks Join Date: Jan 2001 Location: Fordland, MO Posts: 3,188	When the guy rebuilt it, he said that almost all of them are mis-advertised. He said it could be brought up to put out 100, but that would require a different stator. I just don't understand why it wouldn't keep it up at 78 amps. Thats running the lights, heater, stereo. Then like I said, if the fans kick on, the lights dim and the stereo shuts off. Would changing it back to a regulator keep it better? Or is the regulator in the alternator sufficient? Thanks, Jeff. __________________ 1971 Cheyenne C-10 w/700R4 and Tuned Port Injection 1969 K5 Blazer w/Tuned Port 2010 2SS/RS Flaming Orange Camaro 2011 K1500 Suburban 2014 K1500 Pickup 2008 Nissan Altima? The wifes' hoopty

12-27-2002, 04:47 PM	#6
jhow66 Registered User Join Date: Jun 2002 Location: Knoxville Tenn. Posts: 3,058	Internal reg. are all right. The guy was shooting a line to get you to spend some more $'s. 100 amp alt=100amps if alt. is right. Had a 37 amp on my 56 Bel-Air--when using all acc. and rad. fan engine would start to miss and then die--turn off fan would run again. Had it upgraded to 63 amp--it puts out 63 amps. Works with everything on now. __________________ 56 Chevy Bel-Air 2dr. HT (purchased new) 71 Chevy Cheyenne SWB PU (502HO) 65 GMC short bed step--work in progress and my gofer

12-27-2002, 04:55 PM	#7
red71cheyenne Back in the sticks Join Date: Jan 2001 Location: Fordland, MO Posts: 3,188	How do I know how much I actually need? Like you said, check it with all accessories running? I have an ammeter, but don't know if it will handle 100amps. It also won't run at less than like 1000 rpm either. When I start it up in the morning, I have to rev the engine to get it to start charging. You know what I mean? __________________ 1971 Cheyenne C-10 w/700R4 and Tuned Port Injection 1969 K5 Blazer w/Tuned Port 2010 2SS/RS Flaming Orange Camaro 2011 K1500 Suburban 2014 K1500 Pickup 2008 Nissan Altima? The wifes' hoopty

12-27-2002, 05:03 PM	#8
jhow66 Registered User Join Date: Jun 2002 Location: Knoxville Tenn. Posts: 3,058	100 amps should be fine. amp gauge will be fine also as it never shows that much. 1 wire alts. are not self exciting hence you have to rev engine to get them started. Once they are charging they will charge at idle until engine is cut off. __________________ 56 Chevy Bel-Air 2dr. HT (purchased new) 71 Chevy Cheyenne SWB PU (502HO) 65 GMC short bed step--work in progress and my gofer

12-27-2002, 05:05 PM	#9
red71cheyenne Back in the sticks Join Date: Jan 2001 Location: Fordland, MO Posts: 3,188	Thanks for the help. When I get it home today, I'll hook up the ammeter and see how much I'm pulling. Jeff. __________________ 1971 Cheyenne C-10 w/700R4 and Tuned Port Injection 1969 K5 Blazer w/Tuned Port 2010 2SS/RS Flaming Orange Camaro 2011 K1500 Suburban 2014 K1500 Pickup 2008 Nissan Altima? The wifes' hoopty

12-27-2002, 06:39 PM	#10
72K10 Registered User Join Date: Dec 1999 Location: New York Posts: 288	Stock without air for our pickups is 43 amps, if I recall correctly, and with air it's 62 or so. 78 ought to be enough to handle a regular load with stereo. __________________ RLTW 70C10 72K10 72K10 Cheyenne 72C10 Cheyenne Super

12-27-2002, 08:55 PM	#11
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	Even 78 amps is a LOT of current. Unless youv'e got a big amp pushing oversized speakers and a pretty healthy subwoofer theres no way you should be getting close to 78 amps. Ive got an oversized moroso racing pully on my 135 amp one wire and I have to rev it up to 2000 or so to get it started but once its charging I never have a problem. Thats even with the AC fan motor , halogen lights and stereo at full volume. I cantr imagine that you'd be pulling more than 40 amps at any given time unless youve got something weird going on or somethings not wired right. Oh wait a minute. The fans kick in? Are you running dual electric fans? If so you probably dont want to run them through the wiring system. A relay directly to the battery ( circuit breaker protected of course ) would be the way to go with a pair of hi current drawing cooling fans if you dont have it set up that way already. __________________ No truck :-( Last edited by mikep; 12-27-2002 at 08:59 PM.



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.