samneric Posted November 28, 2007 Share Posted November 28, 2007 Hi all, Had dipping volt (I guess amps when running) gauge on my dash and finally switched out the alt with a spare when it struggled to start. With the spare in place, the gauge stayed nicely in the middle of the range for a while then all of a sudden started rising with the speed of the engine, kinda in parallel with the tach. The car got home ok but wouldn't start in the morning. The alarm led is flashing but the dash doesn't light up with the key set to ignition. Tried jumping it with another car but still not even faint dash lights. Could this be something fried by the wack voltage increase??? My only other guess is the alarm (viper) is imobalising the ignition. Any ideas where to start ? ? Steve Link to comment Share on other sites More sharing options...
Durania Posted November 28, 2007 Share Posted November 28, 2007 I had a bad wal-mart battery once give me some issues like you described. Link to comment Share on other sites More sharing options...
nipper Posted November 29, 2007 Share Posted November 29, 2007 A battery is a bunch of plates. As a battery ages, it sheds materials off the plates. Eventually that material can short out the plates and the battery wont hold a charge or allow the car to be jumped. How old is the battery. You may need an altenator too, as the shorted plates can kill an altenator. Have you tried leaving the jumper cables on the car for ten minutes, then trying to start it. nipper Link to comment Share on other sites More sharing options...
samneric Posted November 29, 2007 Author Share Posted November 29, 2007 Thanks for the quick response y'all. The battery is relatively new (within a year) and is a Duralast Gold which always did me well. I haven't tried the jumpleads for 10 mins trick so I'll give it a go... Is there a way to tell it's charged because I get a good voltage (12) but my voltmeter only shows amps up to 20 and then I guess there has to be a load to draw the amps. I also charged the battery from my other Brat all day with my charger and that also didn't seem to put out power. bizzare. My old alt was probably the orig and was definately on its way out so maybe that killed the battery - I hope not - those things are 80 bucks! Steve Link to comment Share on other sites More sharing options...
mudduck Posted November 29, 2007 Share Posted November 29, 2007 How many volts was the meter in the car showing? If it was reading any higher than 15 volts, your alt might have been overcharging and could have fried the battery. Link to comment Share on other sites More sharing options...
samneric Posted November 29, 2007 Author Share Posted November 29, 2007 How many volts was the meter in the car showing? If it was reading any higher than 15 volts, your alt might have been overcharging and could have fried the battery. The gauge was revving all the way up to the top with the engine rpms..... Ut Oh... Link to comment Share on other sites More sharing options...
Durania Posted November 29, 2007 Share Posted November 29, 2007 The battery that went bad in my hatchback was just 6 months old. You might just want to wait till payday and replace them both. Gives you peace of mind at least. Link to comment Share on other sites More sharing options...
mudduck Posted November 29, 2007 Share Posted November 29, 2007 The gauge was revving all the way up to the top with the engine rpms..... Ut Oh... Overcharging alt. Hopfully the battery was all that fried. Really suggest replacing the alt. before tossing another battery in there. Link to comment Share on other sites More sharing options...
xoomer Posted November 29, 2007 Share Posted November 29, 2007 depending on the year... voltage regulator... Duralast.... 2 year free replacement... Alternator... If you have an ea81 you can use my warrenty... and get a free replacement. Link to comment Share on other sites More sharing options...
nipper Posted November 29, 2007 Share Posted November 29, 2007 overcharging altenator can cause what i described too. nipper Link to comment Share on other sites More sharing options...
Cougar Posted November 29, 2007 Share Posted November 29, 2007 You stated that dash lights didn't work when you tried jumping the battery from another car. Assuming that the jump was connected correctly this would probably indicate that the main fuse has blown in the panel under the hood, or fusible link, if this is an older car. I assume you have a voltmeter in the dash and not a ammeter. You can't measure amperage using a voltmeter. As was mentioned there is a regulator problem if the voltage exceeds 15 volts while the system is charging. It sounds like second alternator is having a problem from what you said after it was installed and it may be due to the battery. If the battery has a shorted cell it will damage the alternator. I suggest you first remove the battery and have it checked out before installing another alternator. Be sure the battery is fully charged before reinstalling it, if it is ok. A discharged battery is very hard on the alternator. Link to comment Share on other sites More sharing options...
samneric Posted December 3, 2007 Author Share Posted December 3, 2007 Thanks for the advice all, xoomer: Thanks for the warranty donation offer. I've been out of town sailing a boat back from Florida (coupla near misses during nighttime fog as tug boat barges navigating the Intercoasted Waterway on autopilot ignored our spot light signals ). So haven't had a chance to respond back with status update.... Upon advice, last Thursday, I changed out the battery and alternator. Still no lights on the dash. I already checked the fusible links so I figured I do a double check.... In the past, the red one had craftily been blobbed back together with solder so with a curious test prod, low and behold, one of the wires was free to flop around. I fanangled it into a more secure resting point on the dab of solder and tried again - BRRRRRRRUUUUUM ! I have never seen a voltage regulator before so if it is the little rascal that screws onto the alt and has a wire connecting to the batt output then the replacement alt I switched in last week didn't have one. So when adding my newly aquired BA recon alt, I swapped over the little device from my original alt before installing. I temporarily re-soldered the fusible link and re-installed my original Duralast Batt and its been running like a champ since I got a refund on the Napa Batt that I had purchased so all is good - a nice new $100 BA alt and a good batt so I'm good to go. I will swap in the red fusible link from my other Brat tonight to complete the job and then go on a hunt for a backup fuse. Anyone know where you can get your hands on one of these strange subie fusible links nowadays???? Steve Link to comment Share on other sites More sharing options...
mudduck Posted December 4, 2007 Share Posted December 4, 2007 You could go to the fealer, but they ain't cheap(at least around here), find some at the pick and pull(subarus are very rare in junkyards around here), or do what I did, use a fuseable link for another make, I think I used one for a chrysler. I took the ends off the original, and crimped them on to the replacement. Been good so far. Link to comment Share on other sites More sharing options...
heartless Posted December 4, 2007 Share Posted December 4, 2007 you should be able to get fusable link wire and ends at your local auto parts store. take in the dead one (make note of the size - # amps - from the box) get enough wire to replace + a little extra, put on new ends of the appropriate size to fit the connections and viola! fixed! Had to do this with my 89 GL when I had no parts cars available to steal a replacement from. Link to comment Share on other sites More sharing options...
Numbchux Posted December 4, 2007 Share Posted December 4, 2007 sounds like you got it mostly figured out... but for future reference. the volt meter reads volts, and only volts, and is completely unaffected by amps. it should read 10-12v when off...and 12-14v when running. anything other than that, and you've got problems Link to comment Share on other sites More sharing options...
samneric Posted December 7, 2007 Author Share Posted December 7, 2007 sounds like you got it mostly figured out... but for future reference. the volt meter reads volts, and only volts, and is completely unaffected by amps. it should read 10-12v when off...and 12-14v when running. anything other than that, and you've got problems Yeah, not sure where I read about it turning to amps after start.... I think it was the Haynes manual Just out of curiosity I was chatting with my Dad last night who explained that the voltage regulators of old (His was a Ford Anglia) consisted of coils and points. Now I can kinda see how a coil could be used to moderate voltage but does anyone know how solid-state regulators work???? Steve Steve Link to comment Share on other sites More sharing options...
cobcob Posted December 7, 2007 Share Posted December 7, 2007 does anyone know how solid-state regulators work???? http://en.wikipedia.org/wiki/Voltage_regulator Link to comment Share on other sites More sharing options...
subiemech85 Posted December 8, 2007 Share Posted December 8, 2007 NO volt output, check t-connector HIGH volt output, no battery connection Link to comment Share on other sites More sharing options...
samneric Posted December 8, 2007 Author Share Posted December 8, 2007 http://en.wikipedia.org/wiki/Voltage_regulator Fair enough Link to comment Share on other sites More sharing options...
samneric Posted January 9, 2008 Author Share Posted January 9, 2008 Sorry for reviving the dead! Since last posting on the thread (when I figured all was OK), the battery would gradually lose its charge. I had it checked with a small machine from Napa and was told that the battery was tested as being able to accept a charge and to check my wires. At this point I changed out the battery terminals along with the connector to the alternator. It was fine until the cold set in and I've had a couple of days with clicks followed by eventual start. So I went to Autozone and had them hook up the "Real" batt/alt testing machine. The battery test (after 45 secs) said it needed a re-charge before a re-test. The alt test measured peak amp output of 2.9 First question - how can I measure amp output myself? I have a fancy multimeter but it only measures up to 20a - I was told the amp test should have read at least 100 peak amps. I'd like to measure the amps from the back of the alt to the battery to trace a bad wire condition. Second question - Could a faulty voltage regulator (afixed to the charge connecter on the outside back of the alt) prevent amps from passing through it? It all seems to point to being able to measure more than 20 amps and I get the feeling a tester that reads in this range is going to be expensive :-\ Thoughts, anyone? Steve Link to comment Share on other sites More sharing options...
nipper Posted January 9, 2008 Share Posted January 9, 2008 Physically describe said charging system testers .... was one silver with a pair of jumper cables, with an analog meter? Looked like some crazy cheese grater? nipper Link to comment Share on other sites More sharing options...
samneric Posted January 9, 2008 Author Share Posted January 9, 2008 Physically describe said charging system testers .... was one silver with a pair of jumper cables, with an analog meter? Looked like some crazy cheese grater? nipper The one from Napa looked like a sophisticated multimeter. It was bigger than your normal device and had various buttons on it along with the two crocodile clamps on cables. The one from Autozone came on a wheel-out cart. It was a bigger machine with bigger crocodile clamps and cables. It was like a small computer. It had a digital readout for volts and amps. As soon as you hooked up the clamps to the bat, the voltage showed. I had to run the car at about 2000rpm before the amp ouput test gave its result. Steve Link to comment Share on other sites More sharing options...
Cougar Posted January 10, 2008 Share Posted January 10, 2008 In order to read high currents you need to use either a current shunt or a current probe. A shunt is placed in series with the lead under test and then you read the amount of millivolts across the shunt as current flows through it. The shunt is calibrated for a certain amount of voltage drop to current flow. Another device that can measure the current is a DC current probe. It is clipped around the lead under test and the current is read. These devices are usually fairly expensive so a lot of folks don't have them on hand. By making sure the alternator can hold a good voltage output while under a high load, is a pretty fair test. Link to comment Share on other sites More sharing options...
nipper Posted January 10, 2008 Share Posted January 10, 2008 I have gotten screwed three times by the computerized testors. Either the techs dont know how to use them or read them. Three times they told me I had a good altenator, I pulled out my old resistor type tester like this http://cgi.ebay.com/ebaymotors/125-Amp-Battery-Tester-ATD-5495_W0QQcmdZViewItemQQcategoryZ43989QQihZ004QQitemZ140194843158QQrdZ1QQsspagenameZWDVW and it told me i had a failed altenator. I replaced the altenator and all my problems went away. See if you can find a shop or a store with one of these. nipper Link to comment Share on other sites More sharing options...
Skip Posted January 10, 2008 Share Posted January 10, 2008 There are dash mounted ampmeters that have the shunt built into them. These were in vogue back in the sixties, many Britsh cars had them (good old PoD -> Prince of Darkness) Problem is the large gage wires needed to be run to and fro the meters. The model Cougar mentions is a better choice for your application. Small gage wires (18 or 20 AWG) can be run to the dash mounted meter. Only the newest style Amprobes measure DC the older units only measured AC. http://en.wikipedia.org/wiki/Clamp_meter Link to comment Share on other sites More sharing options...
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