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Technical Charging issues on maiden voyage, I am stumped.

Discussion in 'The Hokey Ass Message Board' started by Roothawg, Jun 15, 2014.

  1. Roothawg
    Joined: Mar 14, 2001
    Posts: 21,617

    Roothawg
    Member

    OK, took mama's wagon out yesterday for the Hot Rod Hundred. It was the first time the car has been driven. Needless to say, we were basically shaking the car down as we traveled. We did 250 miles but it was a long 250 miles.

    I had issues with the battery dying along the route. The battery ( PC925 Odyssey ) was charged overnight on a battery charger, so it was ready to go. The alternator is a CS GM alternator 105A. The only electrics on the car besides the gauges are the electric fuel pump, an electric fan and the HEI. The battery would start to go dead after about 40 miles. It reads that it is putting out 14.9 volts when disconnected from the battery. All parts are new and the wiring harness is new.

    I can disconnect the hot lead and it will run for about 15 seconds and then die like you shut the key off.

    The way we could tell we were getting close to having a dead battery is the car would start running rough and the GPS, we were using for our speedometer would start wigging out.

    It only has 2 wires, the exciter wire and the charging wire.

    What could be going on here?
    I can't be limited to a 40 mile range.

    Thanks for your input.

    Root
     
  2. Root,is it a old battery or new? HRP
     
  3. Roothawg
    Joined: Mar 14, 2001
    Posts: 21,617

    Roothawg
    Member

    Brand new, maybe 6 weeks old.
     
  4. Roothawg
    Joined: Mar 14, 2001
    Posts: 21,617

    Roothawg
    Member

    I am wondering if too much voltage can damage the gel cell battery? I just went out and disconnected the output lead and it was reading 15.1V. It is the second alternator in a week.
     

  5. tfeverfred
    Joined: Nov 11, 2006
    Posts: 15,792

    tfeverfred
    Member

    That's a lot of extra voltage floating around and why so much amperage on your alternator? 105a? I'd expect that if you had air bags or a HUGE stereo system. Try a battery that reads the normal 12v and 13.7 when it's charging. Also, check the regulator or maybe swap alternators.
     
  6. Roothawg
    Joined: Mar 14, 2001
    Posts: 21,617

    Roothawg
    Member

    The alternator was a factory GM alternator for the Suburbans. It was what was on the bracketry that the previous owner had installed, so I am kinda stuck with what will interchange.

    The alt is internally regulated. This is the second alternator in a week. Not saying that it cant happen, but I would hope that with new alternators, they would at least test them for output.

    The sense wire is not connected, as per Haywire, the wiring provider. I just wonder if I made a jumper from the sense pin to the output post if it would control voltage output more accurately.
     
    Last edited: Jun 15, 2014
  7. tfeverfred
    Joined: Nov 11, 2006
    Posts: 15,792

    tfeverfred
    Member

    Any GM alternator, factory or after market, will work. I'm running a GM 65amp and an extended life (bullshit) parts store battery. You think that alternator may be frying that battery? Worth a look.
     
  8. With the oddy bat- We run them at work,and low and behold,there are "special" chargers,and charging procedures for those. In a loaded cop car,with all the bells and whistles,draw is still at a factory spec=milli amps.(the car)-not the goodies= IE computer,lighting,etc..... I would suggest- having the battery checked by an oddy dealer. They are warrantied for TEN years! We get two before they crap out.
    Heavy buggers they are....
     
  9. Root,do you have a local guy that can test your alternator?

    and do you have any inline bullets,sorta like a fuse where there may be a loose connection? HRP
     
  10. Roothawg
    Joined: Mar 14, 2001
    Posts: 21,617

    Roothawg
    Member

    HRP, I have a fusible link crimped on the power output wire. I checked it for opens and it checks good.
     
  11. Do you have a volt gauge? and do you see it dropping while you drive? HRP
     
  12. walker
    Joined: Dec 29, 2008
    Posts: 217

    walker
    Member

    No sense line would equal no voltage regulation, would it not, or high output, which would kill a battery in short order. Can you post the wiring diagram you followed?
     
  13. fortynut
    Joined: Jul 16, 2008
    Posts: 1,038

    fortynut
    Member

    I read this and my first thought was: Do you have a ground cable installed from the body to engine? If the battery is grounded to the frame and not the engine, it more than likely there is a faulty ground that will play hell with the battery charging because it is sometimes on and sometimes off again, depending on a lot of variables. And, even though it will crank and run, voltage going to the battery won't replace what is being drawn out. Just a thought. I know there are guys on here a hell-of-a-lot smarter than me when it comes to electronics, but I've lived through a lot of nightmares, some of my own making.
     
  14. tommy
    Joined: Mar 3, 2001
    Posts: 14,757

    tommy
    Member Emeritus

    shouda used a generator.:D:D
     
  15. Engine man
    Joined: Jan 30, 2011
    Posts: 3,476

    Engine man
    Member
    from Wisconsin

    It sounds like the alternator is not connected to the battery. With alternator connected and the engine running, check the voltage at the alternator and at the battery positive terminal. There will be a slight difference but both should be at least 13.6 volts. For a 105 amp alternator you should have at least a 10 ga. wire.
     
  16. I'm a bit confused here,
    I'm reading that the alternator is on fact producing but the battery isn't taking it ?

    Is the alternator working for a short time then dies?


    Do you have a picture of the plug and pigtail with a reference to the letters on the alternator ? I had a similar problem with a swap and needed to repin the plug.
     
  17. 1oldtimer
    Joined: Aug 21, 2003
    Posts: 8,023

    1oldtimer
    ALLIANCE MEMBER

    For the CS130 alt the sense wire is hooked to the battery lug on the rear of the alt. I would charge the battery and give it a good load test to make sure it's ok. Swap the wiring and check the charging with the system intact, 14.5 volts is good and if you can check the amps while running (a VAT40 or amp clamp will do good). With nothing on you might see 30-50 amps (depends on battery condition), then with a load it will get closer to max amp output. By checking with the battery cable off your only seeing the alts max volt output, not what it's really putting out while you drive. Also as said above you can't have enough grounds (from engine to frame, frame to body, engine to body). Also when you checked the alt output was it after you replaced it with a new one? or after it died while re charging the battery?. Over charging will hurt the battery and kill the alt if left too long. Check out the battery really good because if the battery is 1/2 good the alt will full charge all the time and burn out. It's really needs to cycle from charging to maintaining to keep it cool.
    [​IMG]
     
    Last edited: Jun 15, 2014
  18. Ulu
    Joined: Feb 26, 2014
    Posts: 1,767

    Ulu
    Member
    from CenCal

    First thing I do when charging goes flaky is test the cables and ground strap from engine to body & frame. How I do it is put a voltmeter on the battery with the engine running, then just add a jumper wire along each cable/strap in turn. Watch the voltmeter & when it changes you've jumped the culprit cable.

    If nothing changes, start suspecting the regulator & alternator.
     
  19. borderboy1971
    Joined: Oct 20, 2008
    Posts: 747

    borderboy1971
    Member
    from Canada

    Dont' forget that it is possible to be charging the proper voltage , but without the proper amperage.
     
  20. squirrel
    Joined: Sep 23, 2004
    Posts: 49,264

    squirrel
    Member

    With the battery connected to the alternator output, and the engine running, what voltage do you see at the battery? If it's less than 13 volts, then the alternator is not charging the battery. If it's more than 13, then it's charging. Pretty simple....if it's not charging, then either it's not wired correctly, or there's something wrong with the alternator (or the belt is slipping, or....etc)

    Measuring the alternator's voltage when it's not connected to the battery really won't tell you anything useful.
     
    Dirty2 likes this.
  21. 55 Ford Gasser
    Joined: Jul 7, 2011
    Posts: 584

    55 Ford Gasser
    Member

    My 2 cents: Never unhook battery cable with engine running if you have an alternator. It's okay with a generator but not an alternator. You can send a spike through the alternator. As said already, make sure there is ground from engine to frame/body. That ground gets missed alot. Like mentioned already, check reading at battery when running, rev engine, see if volts increase. Good luck and let us know when you find the problem.
     
    26 roadster and Dirty2 like this.
  22. easy way to see if alternator is charging is start vehicle and take a screwdriver or wrench and touch the center of the back and see if their is a magnetic draw and if their is it's working. lots easier and quicker than parts store test.
     
  23. stimpy
    Joined: Apr 16, 2006
    Posts: 3,547

    stimpy

    on the newer alts you have to hook up the sense wire or you can fry the alternator or your wiring , if its reading 14.9 its trying to charge max load and with a a alternator you need electricity to make electricity and what its doing is pulling more amps trying to recharge a full battery ( cooking the battery ) and draining the system . and never pull the battery off the alternator with it running as it can make the regulator short out and they can spike to 120+ volts and burn up everything in the system before it cooks itself . hook up the sense wire thru the ignition switch or a light like they do on factory cars . or thru a diode and a wire going to the battery , never hook off the back of the alternator as its a dirty and incorrect signal , it should see the battery as the battery acts like a condensor and smooths out the load and the alternator then sees if the battery really needs any feeding .
     
    gas pumper likes this.
  24. Roothawg
    Joined: Mar 14, 2001
    Posts: 21,617

    Roothawg
    Member

    Ok, I'll see if I can address the concerns.

    1. Yes, I have a ground from the battery to the engine. I also have a battery to frame ground and also an alt case to batt ground.

    2. I do have a amp gauge, but decided not to use it, due to safety concerns. I have not had a chance to order a volt gauge.

    3. The schematic listed above, fig 82c is how it is wired. However, I used a 470 ohm, 1/2 watt resistor on the "L" terminal as per my technical advisor at haywire and the sense line isn't connected to anything, which is my suspect personally.

    4. It is a 10 gauge wire on the charging circuit.

    One thing I should note, the alternator felt extremely hot to the touch. I think it never cycles out of charge mode, if that helps.

    If I missed anything I apologize.

    Thanks for the input guys.
     
    Last edited: Jun 15, 2014
  25. squirrel
    Joined: Sep 23, 2004
    Posts: 49,264

    squirrel
    Member

    If the sense line is not connected, it thinks there is zero voltage on the battery, and should give "full field". I think.

    Don't you have a test volt meter, you can measure the voltage at the battery with when it's running?
     
  26. Roothawg
    Joined: Mar 14, 2001
    Posts: 21,617

    Roothawg
    Member

    Yes, I have checked it. But, couldn't see much of a difference between the battery and the alternator. The reason is the output goes directly to the battery, so when reading at the terminal it's hard to differentiate.

    Look at these adapters. All of the have 2 wires. Mine has 1.
    http://www.qualitypowerauto.com/catalog.php?item=81

    I think the W1220 is the adapter I need.
     
  27. squirrel
    Joined: Sep 23, 2004
    Posts: 49,264

    squirrel
    Member

    well...what is the voltage at the battery when the engine is running, and the alternator is connected to the battery?
     
  28. Roothawg
    Joined: Mar 14, 2001
    Posts: 21,617

    Roothawg
    Member

    I'll check it tomorrow when I get home. I'll check it running and not. I can't remember off the top of my head. It's been a long weekend and my brain is fried…..
     
  29. 1oldtimer
    Joined: Aug 21, 2003
    Posts: 8,023

    1oldtimer
    ALLIANCE MEMBER

    Yea, you need 2 wires or the alt won't be able to monitor the charge rate. It sees a dead battery right now and it working it's ass off to charge it back up, so the case will be hot. The other terminal is working since the alt is charging. Easy test is to hook up a volt meter to the battery (with the system intact, no wires off), check the voltage while it's running, then with a jumper wire tap into the "S" pin on the connector, attach other end to the battery lug on the alt rear and re check volt meter readings. If it goes down to a normal range you need to add the wire.
     
  30. stimpy
    Joined: Apr 16, 2006
    Posts: 3,547

    stimpy

    and do not try to use the amp gauge it will burn it up as the alternators output will exceed it greatly and cause a melt down internally in the gauge , get a volt meter

    as squirell said in #25 the alt is seeing a dead battery and the alt is going into max charge and thats why its hot ( when a electromagnet ( field) sees full charge it gets hot )
     

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