Alternator recommendations

[joemomma]

On the way home yesterday - actually it began as soon as I started the car to go home. Battery light came on and I noticed voltmeter was a good bit lower than it usually sits. First thought was alternator losing it, so I killed all accessories and HVAC and started for home. Voltmeter was continuing to drop, but I managed to barely get it home. At one point, several other idiot lights came on and the tach stopped working, but I made it home.

Anyway - seems I'm in the market for an alternator. Anyone have any recommendations?

I'm guessing this is the factory alternator and it finally gave up the ghost - it had a pretty good system in it when I got it, and I have since replaced that with a comparable system due to some failed components. So, are the SVE 130A any good? I don't really want to spend $250 for a PA, unless the SVE is junk. What about the stuff from VatoZone/etc?

 

[ttocs]

it is normally just the voltage regulator that goes out and they can be replaced. Youtube shows how and from what I remember it was one of those things that I found after I replaced my alt, but I might have tried this had I known.

 

[joemomma]

I pulled the trigger on the SVE 130A from LMR. In my reading I learned that flaky alternator can lead to all sorts of weird/random issues, makes me wonder if some of my idle and rough running issues were related. I'll know soon enough, I have the IAC restrictor plate in hand and can test this weekend hopefully (assuming I can get the car charged enough to run).

 

[joemomma]

Got the new SVE 130a alternator installed, and no joy still. Battery shows a little over 12v with the car off, and the same with it running. Alternator shows about 12v testing across battery negative and alternator output post. Checked the fused link and it showed continuity, so I don't think it's bad. Any other stuff to check - fuses or anything?

I posted on the SN95 FB page and one guy said he had a similar issue and it was a ground problem, he ran a ground from the alternator bracket to frame and it fixed it. Another guy mentioned upgrading the wire to the fuse box from the alternator. Open to suggestions from the experts here.

 

[ttocs]

what year was this in? I thought I remember that some of the models have some part in the gauges that can go bad and cause problems. By chance does the car beep for 30 secs after you start it? If so it is trying to tell you that you have a warning light out and if the alt warning light is out I think it can cause some issues in the circuit.

 

[joemomma]

It's a '94. No beeping or anything, and the battery light is on in the dash.

 

[Mustang5L5]

I'm not 100% on the SN 5.0's, but they are somewhat similar to the Fox. There's a fusible link (on the fox cars) that supplies voltage to the regulator on the alt. If there's no voltage here, the regulator doesn't activate and you will get the battery light on.

Should be 12V on 1 or 2 wires on the 3-pin plug on the alt. I'm not 100% but i do have a 94-95 alt on my Fox, so I do know the systems are close enough to be compatible. The single pin wire also needs a solid connection for the alt to work as well.

If i had a 94-95 diagram I could be more specific.

 

[joemomma]

The SN have the fusible link as well - I checked it for continuity but I didn't check any wires on the plugs (there's a 3 pin and a single pin connector).

 

[lwarrior1016]

The 3 pin connector should have a white wire that goes over to the single pin. Then there should be a yellow and a green wire. The yellow should be battery 12v and the green should be key on 12v.


This is all off memory, but I think this is all correct.

 

[lwarrior1016]

The bulb in the gauge cluster completes the excite circuit and that’s what turns the alternator on (the green wire at the alternator). You said the light is on, so it shouldn’t be the bulb. I’d check the connector at the alternator and make sure it’s got the powers it needs.

 

[ttocs]

IIRC the bulb comes on when it does its testing or there is a problem but I thought there was a resistor in parallel to the bulb that if it goes bad can cause problems? I can't find my wiring bible....

 

[joemomma]

I'll check the connectors this eve.

 

[dalpoas83]

 

[ttocs]

yes that 510 ohm resistor is what I am talking about. I think if it starts to fail it leads to strange problems that are hard to find. Now where that is, I do not know....

 

[joemomma]

Checked all grounds and they appear good. I ran a new ground from the alt bracket down to a motor mount and no change. I didn't have a chance to check the connectors for power.

EDIT: could it be the battery? This battery is about 3 years old, give or take. It was completely discharged when the car was in the body shop getting painted, so I wonder if it has issues. It does show a bit over 12v across the terminals after being charged.

 

[joemomma]

Per the Ford Service Manual, it looks like there is a 20A fuse in the engine compartment fuse panel for the ALT. I'll check that too.

 

[joemomma]

Well slap me silly, turns out the 20A fuse was blown. Replaced that, and everything is working. Glad it's fixed, but pissed it took me a new alternator and 6 hours of chasing my tail to fix it. On the bright side, I have a new alternator.

 

[GTamas]

Well slap me silly, turns out the 20A fuse was blown. Replaced that, and everything is working. Glad it's fixed, but pissed it took me a new alternator and 6 hours of chasing my tail to fix it. On the bright side, I have a new alternator.

There was some reason why the fuse blew, so maybe it's really not bad to have the new alternator.

 

[Mustang5L5]

Well slap me silly, turns out the 20A fuse was blown. Replaced that, and everything is working. Glad it's fixed, but pissed it took me a new alternator and 6 hours of chasing my tail to fix it. On the bright side, I have a new alternator.

Glad you found it. No fuse on the fox cars, so without that wiring diagram up above I would have never known the SN cars had a fuse as well.