External Regulator to CS144 Conversion - The 1947 - Present Chevrolet & GMC Truck Message Board Network

bradh · 10-12-2010, 10:55 PM

I'm converting a '72 C10 with external regulator to a CS144 alternator. I plan to add AC and a MKVIII fan so I figure it's a good time to upgrade the charging system. I scored a 220 Amp "Stinger" (never heard of them) CS144 at a swap meet for $10. I figured if nothing else it was a good core. I took it to the parts store and they threw it on their tester and it indeed was putting out 220 Amps and 14 to 15 volts. It had a broken fan so they dug through their pile of spare stuff from cores and hooked me up with a free fan. They also supplied me with the CS pigtail for about nine bucks.

I unplugged the external regulator and spliced the blue and brown wires together. On the back of the CS144 I connected the heavy S wire to the battery terminal on the back of the alternator and connected the L wire to the original blue wire on the alternator plug. I also ran a heavier gauge wire from the battery terminal on the alternator to the battery. My truck does not have a factory warning light to excite the field on the alternator, it has an amp gage. Do I need to add a resistor or warning light or is there resistance built into the system already? I started it up and it's putting out 14.8 volts so it is charging. I just don't want to mess up my "new" $10 alternator. Thanks.

Brad

dwcsr · 10-12-2010, 11:02 PM

I added a 75 ohm resistor to mine.

gkesseru · 10-13-2010, 08:07 AM

You need to add either a resistor or lamp or both into the L circuit or else the regulator will eventually burn out.
see http://www.alternatorparts.com/cs130_sbpage3.htm

**VetteVet** · 10-13-2010, 01:32 PM

The gauge dashes have a resistance wire from the key switch to the external regulator that has about 10 ohms of resistance. This is the brown wire. The blue wire completes the circuit to the alternator. The plug on the old 10 SI alternator is different as you know and the website I linked shows the plug for a newer SI that has the internal voltage regulator. He's doing an upgrade to the CS style like yours.

If you did not have a resistance in the brown wire, then the alternator would not charge, which is why when you started the engine it charged because the 10 ohms was enough to excite the alternator. The problem is that 10 ohms is not enough to protect the CS alternator. The experts recommend at least 30 ohms and DWRSC is right. 75 ohms is better and a 3 watt value. This is what painless wiring recommends for their harnesses. The website I linked gives the value and they are very inexpensive.

http://temp.corvetteforum.net/c3/zma...ternator01.htm

bradh · 10-13-2010, 04:04 PM

I'll just add a resistor inline and I'll be good to go. Thanks for the help.

This thing pretty much dropped right into my factory brackets and was a VERY easy swap if anyone else is considering a CS144. I may need to go for a size longer on the belt since I might be able to fit a sheet of paper between my alternator and the valve cover but I also have RHS heads and they have a raised gasket rail. I'm running short valve covers.

Brad

10-12-2010, 10:55 PM	#1
bradh Registered User Join Date: Jan 2007 Location: Nebraska Posts: 84	External Regulator to CS144 Conversion I'm converting a '72 C10 with external regulator to a CS144 alternator. I plan to add AC and a MKVIII fan so I figure it's a good time to upgrade the charging system. I scored a 220 Amp "Stinger" (never heard of them) CS144 at a swap meet for $10. I figured if nothing else it was a good core. I took it to the parts store and they threw it on their tester and it indeed was putting out 220 Amps and 14 to 15 volts. It had a broken fan so they dug through their pile of spare stuff from cores and hooked me up with a free fan. They also supplied me with the CS pigtail for about nine bucks. I unplugged the external regulator and spliced the blue and brown wires together. On the back of the CS144 I connected the heavy S wire to the battery terminal on the back of the alternator and connected the L wire to the original blue wire on the alternator plug. I also ran a heavier gauge wire from the battery terminal on the alternator to the battery. My truck does not have a factory warning light to excite the field on the alternator, it has an amp gage. Do I need to add a resistor or warning light or is there resistance built into the system already? I started it up and it's putting out 14.8 volts so it is charging. I just don't want to mess up my "new" $10 alternator. Thanks. Brad

10-12-2010, 11:02 PM	#2
dwcsr Hollister Road Co. Join Date: Apr 2005 Location: Houston Posts: 6,134	Re: External Regulator to CS144 Conversion I added a 75 ohm resistor to mine.

10-13-2010, 08:07 AM	#3
gkesseru Registered User Join Date: Dec 2009 Location: California, Maryland Posts: 544	Re: External Regulator to CS144 Conversion You need to add either a resistor or lamp or both into the L circuit or else the regulator will eventually burn out. see http://www.alternatorparts.com/cs130_sbpage3.htm __________________ 72 Fleet (died) 78 Step (sold) 55 Step named Fred (sold) 00 F150 68 Step (named El Scorcho by PO) Build thread for the new El Scorcho http://67-72chevytrucks.com/vboard/s...d.php?t=392932

10-13-2010, 01:32 PM	#4
VetteVet Msgt USAF Ret Join Date: Jan 2005 Location: Kalamazoo, Michigan Posts: 8,707	Re: External Regulator to CS144 Conversion The gauge dashes have a resistance wire from the key switch to the external regulator that has about 10 ohms of resistance. This is the brown wire. The blue wire completes the circuit to the alternator. The plug on the old 10 SI alternator is different as you know and the website I linked shows the plug for a newer SI that has the internal voltage regulator. He's doing an upgrade to the CS style like yours. If you did not have a resistance in the brown wire, then the alternator would not charge, which is why when you started the engine it charged because the 10 ohms was enough to excite the alternator. The problem is that 10 ohms is not enough to protect the CS alternator. The experts recommend at least 30 ohms and DWRSC is right. 75 ohms is better and a 3 watt value. This is what painless wiring recommends for their harnesses. The website I linked gives the value and they are very inexpensive. http://temp.corvetteforum.net/c3/zma...ternator01.htm __________________ VetteVet metallic green 67 stepside 74 corvette convertible 1965 Harley sportster 1995 Harley wide glide Growing old is hell, but it beats the alternative. Last edited by VetteVet; 10-13-2010 at 01:35 PM.

10-13-2010, 04:04 PM	#5
bradh Registered User Join Date: Jan 2007 Location: Nebraska Posts: 84	Re: External Regulator to CS144 Conversion I'll just add a resistor inline and I'll be good to go. Thanks for the help. This thing pretty much dropped right into my factory brackets and was a VERY easy swap if anyone else is considering a CS144. I may need to go for a size longer on the belt since I might be able to fit a sheet of paper between my alternator and the valve cover but I also have RHS heads and they have a raised gasket rail. I'm running short valve covers. Brad



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