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| Cs130 conversion problem; no charge at idle?? | |
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| Tweet Topic Started: Apr 16 2015, 02:36 PM (859 Views) | |
| Hotrodray1 | Apr 16 2015, 02:36 PM Post #1 |
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Over Educated parts guy
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I did a conversion to a cs130 alternator and it works great all the time but at Idle. Any one have any Ideas what to try right now I have to keep it idled about 1200rpm to keep it charging. Thanks! |
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| banginmetro64 | Apr 16 2015, 03:36 PM Post #2 |
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is the alternator new or from a jy? mine did the same thing. i swapped for a new unit and all worked out great. it had bad bearings causing charging issues at lower rpm. |
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| t3ragtop | Apr 16 2015, 04:01 PM Post #3 |
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Turbo3 and Twincam Tweaker
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i'd have to agree. mine makes 42 amps @ 14.3 volts idling at 1000 rpm. and that's with a 4" under drive pulley. with a stock 5" accessory pulley you should have a higher alternator rotor speed making closer to 50 amps at rated voltage at 1000 rpms. you also should have full output amperage of 105 amps at around 2750 rpm. ray, i just thought of another thing. the cs130 also comes in a single wire model that looks exactly like the 3 wire model. the one you need fits a model range of chevy and gmc c/k/g pickup trucks between 1985 and 1991 with the top ear located at 11 o'clock. |
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| Hotrodray1 | Apr 16 2015, 07:02 PM Post #4 |
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Over Educated parts guy
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My alternator is completely remanufactured I took it next door to where I work. They were just going to fix it but owners son completely remanufactured the alternator turned armature new bearings,brushes and new voltage regulator for $20.00. owner of alt starter shop said enjoy. I have tested it 2 times so I know it works |
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| t3ragtop | Apr 16 2015, 09:23 PM Post #5 |
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Turbo3 and Twincam Tweaker
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well, then don't sit around idling. ![]() i usually fire the engine up and as soon as i have stable oil pressure i'm driving. still, ray, the cs130 in my car with the under drive pulley which increases alternator rotor speed by 20% puts out 40 amps at idle right after starting the engine. cranking the starter puts way more load on the battery than almost anything else and it drops the charge level enough that the first five minutes after a start has the alternator bringing the charge back up, then i can see my volt meter drop to around 12.5 volts as the regulator tapers off the charging rate. if i'm running large electrical load items like the hid headlights, heater blower, and stereo i see a change in the charging pattern. is it possible that your car is drawing so little current at idle that the output you see is sufficient to keep up with the charge? if you increase the electrical load does the output increase? when you test an alernator the machine uses a big ass load resistor that maintains maximum load on the alternator. i put together some data on my cs130's output at various rpm by connecting my load tester's resistor to the battery to maintain a constant high load while i was researching the effects of different diameter pulleys in an attempt to tweak the alternator's rotor speed. it turned out that the pulley that came on my cs130 alternator was the best one with the under drive pulley. maybe the under drive pulley is the secret.
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| Hotrodray1 | Apr 16 2015, 09:57 PM Post #6 |
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Over Educated parts guy
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I am going to drive it to GOTG then I will worry about it. I need some thing to do next week while on vacation! I run the idle speed up to almost 1200rpm for now till I get back. I had headlights,wipers and blower motor on high I know that was more than enough load to get it to charge. I did not check output last night at 11 with it raining like cats and dogs. I just kept it moving.I checked voltage output this morning it was 14.8 volts when all the loads were on at 1200 rpm.Drop below and it would drop off quickly down to 12.9 so it was still charging but not enough to keep light off on dash. |
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| Hanuman | Apr 17 2015, 01:38 AM Post #7 |
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"The Almighty Grounds Cleaner"
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if lights on the dash your not charging. the charge light grounds through the alternator out put windings........when the alternator out put excedes the voltage of the battery, the current no longer can ground so the light goes out. in simple terms, if the charge light is on, the alternator is outputting less than 12.6 volts.......its not supplying a charge. have you done a voltage drop test yet? #1: using your digital dvom, positive to positive charging post on alternator, negative to alternator case. record voltage. #2: postive to battery positive, negative to battery negative. record voltage. #3: is more than 0.2 voltage drop replace cables. |
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| t3ragtop | Apr 17 2015, 06:26 AM Post #8 |
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Turbo3 and Twincam Tweaker
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good point h'man. i use 4 gauge ground and 100 amp fused supply cables to the battery and leave the factory 6 gauge cable with the quick clip on the fuse and relay rack. |
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| Hotrodray1 | Apr 17 2015, 08:20 AM Post #9 |
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Over Educated parts guy
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I am adding another cable to Battery and doing a voltage drop test today before i leave for GOTG. |
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