Alternator woes - Need some help

[JAStirrett]

Ok guys, my sr20 alternator recently took a dump on me, so like everyone else has thought and done, I installed a Quest alternator because of the extra amps (double fuel pumps, radio, speakers, etc). Well, it started off by me pulling one from the local junk yard and then going to straight to the parts store to have it tested... It tested good. I installed it and being that I was excited to get the car on the road, I immediately took it out without checking my voltage readings with a multimeter. I got about 10 miles away and the car shutoff.

Long story short, I tested the voltages at the battery and directly at the alternator and I was only getting about 11.89ish. I did the redneck troubleshooting because I was unconfident about my voltage readings, so with the car running, I disconnected the battery and the car immediately shutoff. So, I was thinking, it has to be the alternator.

I ordered a new quest alternator from eBay
http://www.ebay.com/itm/160997232094...%3AMEBIDX%3AIT
I realize that it is an "eBay" alternator, but the junkyard alternator that tested good gave me the same readings..

I checked all fuses and fusible links. I just dont understand why I am getting only 11.3 testing directly off the alternator. Anyone with some insight would be greatly appreciated. Is there for some reason that this alternator just won't work on our cars because of an internal regulator or something? I have read that we can use the 125 amp alternator from a Quest. Is there something I am missing? Also, does it matter which screw hole the harness is grounded on the alternator body (8mm screw)? The reason I am asking that is because in the schematic, on the alternator it self it shows an E.

***The pictures were taken with the car running***

[JAStirrett]

Ok, giving an update and hopefully someone can explain this.

I went back out and thought to myself, "Does the rotation of the alternator matter and should I put on the sr20 pulley?"

So with the multimeter hooked up, I started to rev the engine and all of a sudden, it started charging. Like I had to wake it up or something. Also another thing that is weird is when I restarted the car, I had to rev it again to get the alternator to come on! Is this normal?

[cotbu]

Yes normal

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[jdm>usdm]

Check out your bulb check relay. Make sure your charge light is coming on with key to ignition position.

[JAStirrett]

Originally Posted by jdm>usdm

Check out your bulb check relay. Make sure your charge light is coming on with key to ignition position.

Thanks for the replies.

jdm>usdm, when I turn the key to the ignition position, the battery light on the dash does NOT illuminate. I will check the bulb check relay and change it with a known good one. Thanks.

[brndck]

my alternator never "kicks on" until I rev the engine over 3500-4k. not sure if its something fucked up in my wiring harness or what. as soon as I let the car warm up for a minute I rev it to around 5k and then its fine. Having a Voltage gauge on the dash helps too

[JAStirrett]

Originally Posted by brndck

my alternator never "kicks on" until I rev the engine over 3500-4k. not sure if its something fucked up in my wiring harness or what. as soon as I let the car warm up for a minute I rev it to around 5k and then its fine. Having a Voltage gauge on the dash helps too

brndck, that's the issue I'm having also and I was just wondering if my wiring was jacked up also, but it seems as if it is normal.

I second the suggestion to add a voltage gauge. That is my next priority.

Thanks for the replies.

[Primo's Silvia]

I'm having a nightmare with my sr as well it does this same thing -________-

[JAStirrett]

Originally Posted by Primo's Silvia

I'm having a nightmare with my sr as well it does this same thing -________-

Ok, so this issue is a lot more common than I anticipated. I guess the best remedy is to add a voltage gauge so you don't get down the road and realize your alternator isn't charging.

I still have to check the "bulb check relay" as mentioned earlier. I hope this fixes the issue.

[cotbu]

You need be at a certain rpm for the alternator to work. This is normal. Usually 25~rpm

This is also true for generator armatures and whatnot. just 3k or so rpm

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[JAStirrett]

Originally Posted by cotbu

You need be at a certain rpm for the alternator to work. This is normal. Usually 25~rpm

Thanks cotbu, the input is appreciated.

[fatduece]

Having to blip the throttle just to get the alternator to start charging is NOT NORMAL. You guys are on crack. My shit starts charging as soon as I start the car. Cold operating temps (RPM around 1200? dont remember as I havent started my sr20 in 3 years) Anyways, cold start and that shit charges the battery right away. It also keeps the battery fully charged after the car warms up and the idle drops to 740-800 AT IDLE. 14volts at the battery ALL DAY, every day.

[JAStirrett]

Originally Posted by fatduece

My shit starts charging as soon as I start the car.

I was thinking the same thing. I am going to check the bulb check relay soon and report back...

[jdm>usdm]

Having that circuit function properly is what allows your alternator to charge at low RPMs at initial start. The fact that your charge light isn't coming on shows that something's faulty.

The white/red wire running to the alternator plug should have 12V with IGN on. Check your 10A fuse at the fuse block in the cabin. I think there might be another 10A fuse under the hood that does something with this circuit too.

When I was wiring my car, I just ran fused power with IGN on to the charge light, then to the alternator thru the W/R wire. I didn't use any relay. Before I wired this up, I had to rev the car like you do to get the alternator to begin to charge.

[rellik27]

Wow I thought I was the only one, same shit happens with my rb25 and quest alternator. I feel it has to do with lower harness. I plan to buy a new one from wiring specialties in the future, but for now it doesn't annoy me enough lol.

[cotbu]

[firejackal]

Check to make sure the lower harness to the alternator isn't cut, or has a short in the connector.

Not your issue per say, but when I first got my s14 it had an issue that the battery would go dead after sitting for a day or two. While driving the battery light would come on randomly, and it would start to overcharge (even made the SRS light on)

I had went through two batteries and two alternators when I decided there was a electric parasite somewhere...
I noticed when the car was off there was a humming sound coming from the alternator. I checked the pinout of the alternator and the harness on the car to discover it was opposite then what it needed to be. I switched the pins and it fixed all those issues I had.

I'm using a new (at the time) denso alternator I bought on amazon, which autozone tested weaker then my original one.

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[AnonymousBlackX]

Originally Posted by brndck

my alternator never "kicks on" until I rev the engine over 3500-4k. not sure if its something fucked up in my wiring harness or what. as soon as I let the car warm up for a minute I rev it to around 5k and then its fine. Having a Voltage gauge on the dash helps too

what does your voltage normally read ?