what can cause my alternator to do this?

**Firebirdformula** · 06-18-2010, 03:33 PM

When i first start my car in the morning my charging gauge stays low and will stay low until i rev it to 2k rpms and then when i drive it drops once and then charges fine throughout the day ?

**Blue28** · 06-18-2010, 04:22 PM

Do you have a UD crank pulley on your car?

**Blue28** · 06-18-2010, 04:46 PM

UD crank pulley?...??.....?

If you do have a UD crank pulley:

Your alt. needs to reach set rpm before it'll will turn on, then it'll stay on until you turn your car off . If you have a UD crank pulley your normal idle speed(RPM) will now will be to low to turn it on; so that's why you have to rev it to get the alt. to turn on.

**sjsingle1** · 06-18-2010, 06:46 PM

alt going out?

**Firebirdformula** · 06-18-2010, 07:16 PM

no everything is stock and it is a brand new alternator

**Firebirdformula** · 06-18-2010, 07:17 PM

i had them test it at advanced but when i started it and it charged fine, it didnt drop at all and the scan said it was in perfect shape we even did load tests and everything turned out good

**MrMasterCraft** · 06-18-2010, 09:26 PM

Originally Posted by Firebirdformula

i had them test it at advanced but when i started it and it charged fine, it didnt drop at all and the scan said it was in perfect shape we even did load tests and everything turned out good

Only 2 possible reasons I can think of, off hand

1) Gauge is faulty. Never heard of one going bad, but it's possible

2) I've had 2 bad alternators check out fine, but have still been bad. Don't ask me how, and you can even call me a liar, but it's happened. Is it a NEW NEW alternator or a Re-Manufactured alternator? I think there's a regulator inside that could possibly be giving you some trouble, especially if it's a re-man...

Just my two cents...

**Firebirdformula** · 06-18-2010, 10:12 PM

its a rebuilt one, but they rebuilt my last one and it was great until my powersteering leaked on it, which is why they rebuilt it again

**Firebirdformula** · 06-18-2010, 10:13 PM

it has all new parts in it

**xmarkx** · 06-18-2010, 10:32 PM

my PS leaked alot of fluid on my alt and it still works....

**MrMasterCraft** · 06-18-2010, 10:37 PM

Originally Posted by xmarkx

my PS leaked alot of fluid on my alt and it still works....

On my red WS6, I went through 4 alternator swaps until I narrowed the problem to a leaking PS pump. Don't ask my why or how I didn't notice any fluid on all those R&Rs. But I was swapping every 6 months. I think it was the hose

**Firebirdformula** · 06-19-2010, 12:10 AM

ya man im bout to say scew it and go to manual steering, andmark your alternator will go out eventually thats what my last one did, it leaked on it then i fixed the leak and then later opn the alternator started spiking and dropping

**Smittro** · 06-19-2010, 04:53 AM

Originally Posted by MrMasterCraft

Only 2 possible reasons I can think of, off hand

1) Gauge is faulty. Never heard of one going bad, but it's possible

2) I've had 2 bad alternators check out fine, but have still been bad. Don't ask me how, and you can even call me a liar, but it's happened. Is it a NEW NEW alternator or a Re-Manufactured alternator? I think there's a regulator inside that could possibly be giving you some trouble, especially if it's a re-man...

Just my two cents...

Nope you're no lier. As a former rebuilder for an automotive shop I know exactly what you're talking about..

Originally Posted by Firebirdformula

it has all new parts in it

Don't hold your breath.... @ the shop I worked @ we used to venier(sp) the old parts that checked out good.. Many folks think they are getting a remanned part with all new internals.. The real truth (NOT calling you a lier @ all) is rebuild shops rarely use all new stuff.. It may look like all new parts from just looking through the vent holes but it's highly doubtfull. Rebuild shops don't make as much money on an old unit with all new internals. Most shops operate under this premis. You could easily have a nice piece of remanned sh&t and never be the wiser. Not all shops use professional rebuilders either, infact most shops only have ONE head rebuilder and all the other folks work under him.. I've worked with "rebuilders" that could'nt even read an ohm/volt meter and did'nt have any understanding of what they were looking/for such as diode trio test readings, com and stator tests. Many over mill the rotor com on the lathe too, instead of just throwing a rotor with an overly worn com out.. Most rebuild shops also fill their units with Hocheemin parts too, meaning the only thing still from Delphi is the housing, everthing else is from China = many defective "new" parts.. Could be something as simple too as an isolator for internal screws and bolts got over tightened, or an old damaged one got reused before they caught it, and even possible the the rebuilder did'nt bother using them. Then off to the test bench for a 10 second check and load test.. Then you get the unit installed on your car where it's expossed to wheather and constant load, and the problem starts again or there are a whole new set of problems that arise.. Bottom line is it's hit or miss with rebuilds

.. If you can I would have to say always buy a new unit. Or have the senior rebuilder specifically rebuild the unit.. The older guys tend to never use the phrase, "thatel work!" and usually will build the unit to the proper requirements.. I've personally pulled units apart that where supposed to have a certain amperage rated stator only to find a reused antique stator for a lesser amprage Alt, nice huh?

**sjsingle1** · 06-19-2010, 04:48 PM

^^^^ the reason i am gunna rebuild my own........parts are not that expensive.......piece of mind is priceless

**xmarkx** · 06-20-2010, 08:37 AM

Originally Posted by Firebirdformula

ya man im bout to say scew it and go to manual steering, andmark your alternator will go out eventually thats what my last one did, it leaked on it then i fixed the leak and then later opn the alternator started spiking and dropping

probably later rather than sooner because I rarely drive it.. maybe once every week and a half

**Firebirdformula** · 06-20-2010, 08:13 PM

haha ya hopefully you get longer out of yours then i did mine but mine leaked a whole reservoir on it

**RyanJM** · 06-20-2010, 09:04 PM

Have to check my PS for leaks. My 220amp alternator wasn't cheap and I don't need a headache. I got it after wasting time with AZ crap since it didn't like my UD crank pulley even with the OD alt pulley. This alternator was worth every penny, no power loss no matter what is on.

**jamessr** · 06-21-2010, 02:43 AM

For what its worth, put a multi meter on it and see for sure what you're getting. I know my gauge shows at times only 10VDC dropping up and down... I put a meter on it and I get 14.85VDC steady.
I'm happy with that

**Firebirdformula** · 06-21-2010, 12:14 PM

alright i will, its now staying in the in the 10volt area =(

**damianj03** · 06-21-2010, 07:41 PM

was told by my instructor that the battery starts the car and runs all of the accessories also while the car is running and the only job of the alternator is to recharge the battery so you could have a low battery that is only taking a partial charge. just tryin to help