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Old 10-04-2012, 07:29 PM
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ArmAir1 ArmAir1 is offline
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CS144 voltage fluctuating at idle?

Just did the CS144 upgrade on my '77 wag (pre SI-12 alternator) and the voltage is fluctuating between 12.5 volts and 13.8 volts at idle . Once the revs come up off idle it shows a constant 13.8 volts. I've have seen conflicting wiring diagrams for this conversion. Some say a resistor is required on the switched 12 volts while others make no mention of it. I've read that it will work with out the resistor, but the regulator will fail quickly. I've also seen conflicts on whether to hook up to the "L" terminal or the "P" terminal. I've got the "s" terminal looped back to the "batt" terminal on the back of the alternator, 4 gage wire from "batt" to starter solenoid and the "p" terminal connected to switched 12V with a 1/4 watt 100 ohm resistor inline, the "L" lead is capped. My switched 12v wire is also powering my electric choke and my HEI distributor (before the resistor). Anyone who's done pre-SI conversion this have the answer?
I did the same conversion on my '79 with the adapter plug and have had no issues.
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79' Wag 360, T-400, QT w/ pt, cs-144, TFI, 4" lift, 33" BFG KM 2's, 15x10 mags, tube bumpers. "Green Machine"

77' Wag 401, T-400, QT, HEI, 4" lift, 35" MTR's, 4.27's, Detroit R / Spartan F, 15x10 steelies, chop-top, full cage, pre-runner bumpers, 8 passenger. "Battle Wagon"

Last edited by ArmAir1 : 10-05-2012 at 12:17 AM.
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Old 10-05-2012, 08:43 PM
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ArmAir1 ArmAir1 is offline
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No one?
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http://s781.photobucket.com/albums/y...gy%20Wheeling/

79' Wag 360, T-400, QT w/ pt, cs-144, TFI, 4" lift, 33" BFG KM 2's, 15x10 mags, tube bumpers. "Green Machine"

77' Wag 401, T-400, QT, HEI, 4" lift, 35" MTR's, 4.27's, Detroit R / Spartan F, 15x10 steelies, chop-top, full cage, pre-runner bumpers, 8 passenger. "Battle Wagon"
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Old 04-01-2013, 12:50 AM
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ArmAir1 ArmAir1 is offline
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Am I wired wrong?

BTT... my battery has been on the way out for quite some time, ready to buy a new one but still has issue with fluctuating voltage at idle and dont want to burn up the new battery. Anyone have any input on this?
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http://s781.photobucket.com/albums/y...gy%20Wheeling/

79' Wag 360, T-400, QT w/ pt, cs-144, TFI, 4" lift, 33" BFG KM 2's, 15x10 mags, tube bumpers. "Green Machine"

77' Wag 401, T-400, QT, HEI, 4" lift, 35" MTR's, 4.27's, Detroit R / Spartan F, 15x10 steelies, chop-top, full cage, pre-runner bumpers, 8 passenger. "Battle Wagon"
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Old 04-01-2013, 09:58 AM
Joe Guilbeau Joe Guilbeau is offline
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Here is your RPM vs. Amperage output chart.

http://oljeep.com/AltTheory17/AlternatorTheoryVersion17R1.htm#Delco_CS_144_RPM_v s_Amperage

The "S-Terminal" is the Sense terminal. This is nothing more than a voltage monitor that constantly measures the output of the voltage that the alternator is developing.

You should monitor the voltage downstream of the alternator and not at the source.

So, run that sense wire from the "S-Terminal" to the RED wire at position 12 on the bulkhead connector on the firewall. This is a good location to monitor the output voltage of the alternator, as this RED wire is the supply to the rest of the jeep and a voltage of 13.25Vdc to 13,85Vdc at this point will be ideal.

http://oljeep.com/gw/elec/77/W-07a.gif

The bulkhead connector can be located at Grid D4, and the RED wire itself is at terminal 12 and identified as "12 Red 10 (6 & 8)" on the drawing.

The reason that your voltage is varying can be illustrated by observing the first link, where the voltage output of the CS144 alternator does not really start to crank out a steady or linear voltage until the RPM's reach 2000 to 3000 RPM's.

In addition, you have the Sense Terminal connected directly to the output of the alternator, so as soon as the alternator begins to output a charge, you are essentially telling it to stop outputing a charge... this coupled with the low RPM's of the engine result in varying non-regulated voltage control.

If you do not want to tie into the RED wire at this location, you can run the Sense wire to to the Starter Solenoid terminals where the positive battery terminal attaches.

Problem solved!
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Old 04-02-2013, 07:19 PM
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ArmAir1 ArmAir1 is offline
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Thanks for the input Joe....that makes sense, I will give that a try when I replace my battery.
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http://s781.photobucket.com/albums/y...gy%20Wheeling/

79' Wag 360, T-400, QT w/ pt, cs-144, TFI, 4" lift, 33" BFG KM 2's, 15x10 mags, tube bumpers. "Green Machine"

77' Wag 401, T-400, QT, HEI, 4" lift, 35" MTR's, 4.27's, Detroit R / Spartan F, 15x10 steelies, chop-top, full cage, pre-runner bumpers, 8 passenger. "Battle Wagon"
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