Skip to main content
Topic: 3g install **go directly to post 50 for drawing (Read 46640 times) previous topic - next topic

3g install **go directly to post 50 for drawing

Reply #15
i was gonna reply in a rather detailed way but you seem to know what you doing as far as accounting for the voltage drop across your connections and compensating for that in your reading.

you also said your battery was new and that is kinda funny as well.

ill babble a little here and you reply,,,,,,,

when you turn on your meter to dc/v, what does it say with the leads not touching?

measure how much """"""AC"""""" ouput you have coming out of your alternator.  take that reading times .707 and that might be your problem.  residual AC due to a not so perfect world regulator might be slightly bubbling your battery and also causing a slight high charge.

I had an alt once that had about 2v ac output at the exact time when it was running about 16vdc ouput at idle.  Cooked the battery to say the least but it did take some time.

im gonna venture to say that your getting too much residual AC ouput due to a diode make/brand/connection issue that is isolated to the suppier(s).

I dont know how your getting it but some piece part is causing it.

are you running an inverter for any ac outlets in your car?  anytime there is a device in your car prducing AC (such as the head end of your alternator) or an inverter (dc-ac), there are always some form of diode responsible for this.  If any one of the many go bad, you will get ac feedback.

ever notice that big ass diode near the eec test connector?  ask about what that things purpose is.
IIRC,, there are a couple (maybe one) diode in the harness loom near the starter relay or alt ouput harness ect along the side with the battery.  check that out cause i think i remember one being in that harness and if its shorted,, you know the deal.

i hate things that are nearly broke but not exactly broke yet!!!!!!  good luck.

3g install **go directly to post 50 for drawing

Reply #16
eric
ill do i write up in my DIY link as well.  You or someone else please check this step by step below and make sure I did not forget a critical step.

3g install **go directly to post 50 for drawing

Reply #17
Multimeter leads not touching = 1, touching = 00.2 (Actron CP7674, not sure why its reading 0.2 now, it was 0.0 last time I used it. I did leave it on overnight though, battery may be finally dying.). I don't use anything AC powered, adapters or such. I'll give the AC readout a try. Have a local supplier of PA Perf alts here in Beaverton, OR (Krazy Koncepts - they have a 9 second (997hp) Mustang) so likely to pick one up. The fact that NAPA had to "order" an "older" replacement alt from another store (only one in the area) because they couldn't replace it with the newer ones/manufacturer they had in stock (also 3G 130A) for some stupid reason is what makes me want to ditch them all together. I can only assume there's a reason for going with a new manufacturer, and I get stuck on the bad end of it all.

The original alt is 2 years old, the replacement is a month old. I put it in and still had the same problems there in the parking lot but they had no way of getting another replacement for me that day so I figured I'd drive it away and try dealing with another location that may be a bit more customer service oriented. It was funny, they tested it in the car and "everything checked out fine". I pulled it out and threw it on their machine. this is when they agreed to replace it. The guy testing it on the car didn't know anything other than ~14.5v (which it was doing as the car had been running for 15 minutes, giving it time to drop down in voltage before it would begin to rise back up again over the next couple hours). All but one of their employees were clueless.

Of course, the PAPerf will probably put out twice the amperage at idle than the NAPA one...electric fan on DCControl comes on at idle and my voltage will start to drop to 13v, along with all lights dimming inside and out. Old one only did this with all accessories on, not only the fan.
1988 Thunderbird Sport

3g install **go directly to post 50 for drawing

Reply #18
Ummmm...I'm getting ~33.5v AC? That doesn't seem too right. I can probe an actual 24v AC wall adapter and get 24v AC though...also works near perfect for setting amplifier gains. Wall outlet gives me 119.6v.
1988 Thunderbird Sport

3g install **go directly to post 50 for drawing

Reply #19
im wondering if your fan isnt spiking the regulator.  the sudden demand for current might be the deal.

3g install **go directly to post 50 for drawing

Reply #20
It shouldn't be doing anything, being on a DCControl setup. Also, I only went out there and probed it with the car cold/no fan running so it shouldn't affect anything as far as I know. I can force it on and test again if that gives any useful information. Not sure if I can completely disconnect the fan controller easily though. 33v seems like quite a bit getting through.

Edit: No change with the fan/controller disconnected from the rest of the electrical system. Everything else is stock, other than relays and such for lights, single wire ran down to the mini starter, etc (no big electrical addons/draw like the fan).

...made sure I wouldn't lose my receipt and have to go on a hunt for it before...and now I can't find it. Must have hid it too well. Even if I get a replace, need to do SOMETHING with the NAPA warranty.
1988 Thunderbird Sport

3g install **go directly to post 50 for drawing

Reply #21
Sure enough, tried the battery out of the 64 tbird and tried hooking my cables up directly to another car's electrical system (bypassing battery in my car) and the same condition happens with ~15v DC/33v AC.

So which alternators do you guys use anyways? I've only heard much about PA Performance, not much else. Just curious.
1988 Thunderbird Sport

3g install **go directly to post 50 for drawing

Reply #22
I have a 3G from a 2000 3.0 Tarus. Works fine for me

3g install **go directly to post 50 for drawing

Reply #23
Manufacturer/remanufacturer though?
1988 Thunderbird Sport

3g install **go directly to post 50 for drawing

Reply #24
I know someone that had a bad PA Performance alternator right out of the box. Really I don't think it matters from whom you buy one...what does count is customer service and warranty. Right now I'm running a Bosch reman from Pep Boys...I believe it's ~$175 US. So far so good, much better than their basic remans (Pro Start?).

3g install **go directly to post 50 for drawing

Reply #25
I'm running a Wilson reman in mine (I work in a shop that does Wilson rebuilds - what can I say?)
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

3g install **go directly to post 50 for drawing

Reply #26
Got the alt replaced (again). Sure enough, the mobile tester didn't find anything wrong with the electrical system, but the machine inside did and its replaced again. Thinking the alt may have damaged my battery, I had it tested indoors and after 10 minutes it spit out an error, saying to replace the battery (they didn't have the error code book?! It lost 150 cranking amps after the charge test)...so I picked up a "cheap" smaller battery to run while I can get my 65 replaced under warranty (Costco...should I upgrade to an Optima for difference in price?).
1988 Thunderbird Sport

3g install **go directly to post 50 for drawing

Reply #27
I would. Optima are good batterys. What I'm getting for mine as soon as money can be spaired

3g install **go directly to post 50 for drawing

Reply #28
Okay, realized that Costco doesn't test the batteries, just take it back like most of their other merchandise and give a cash refund. Cheapest I can find a Yellow Top is $160 up the road.

Sorry for getting off topic in this thread, but I don't even know what it was started for :dunno: What emails? It seems like this was meant as a private message or something.
1988 Thunderbird Sport

3g install **go directly to post 50 for drawing

Reply #29
For all those that don't know, what can you get a 3G from. And what of those have the different "levels" of power?