Charging sys Issues

[Pumpkn210]

The Pumpkn quit charging. I changed the alt for a good one I had lying around. Didn't fix it. There is a two wire plug that goes into the back of the alt in a T formation. I got power on one of them with the key on. I seem to remember that they should both have power when the car is running. I ran a hot wire to it and it is charging now.

My question is this: Is there a usual thing that this is and do you guys know where that wire goes to? I gotta go get a manual for the diagram but if you guys know where it goes I could prolly fix it without paying for a Haynes book of crap and try to find a Factory Repair Manual.pdf.

[thisismatt]

 

 

Depending on if it's externally or internally regulated. These are for a 510 but should be similar. The lower "leg" of the T connector should be connected with the BAT dummy light, which has +12v power through the light to the alt. When the alt fails, or at startup, the lower leg of the T connector is grounded, causing the BAT dummy light to illuminate. You should not connect the lower leg of the T connector straight to battery for this reason.

[ggzilla]

Stuff like this for B310 is at Datsun1200.com Wiki.

 

Yes, it has the factory Datsun internally-regulated alternator.

* The S wire goes to IGN+, so check your fuses. Most commonly a fuse is blown. It should have + at this wire when key is on

* The L wire goes to the dash light, so you'll see - on it when it is *not* running key on. with alternator putting out power, you see + on it

[DaTsUn72WaG]

my datsun has a bad voltage regulator its not letting the alternator put out enough voltage. 10 amps intead of like 20 at 2500 rpm. idk if the regulator is adjustable or not or where to get one. lol, its sad when you have your lights on and you hit the brakes to stop at a light and you can watch the headlights dim xD

[ggzilla]

The regulator does not control amps. It only controls voltage. Check your output with a voltmeter ... if it is between 13.5 and 15, the regulator is fine. Yes, the original-type (tall) regulator is adjustable but is extremely tricky to adjust.

 

If the volts are OK, but it doesn't put out enough amps, there may be burnt-out diode in the alternator. Or you may have a wiring problem.

[datzenmike]

For the cost of a new regulator, that often go bad anyway, get an internally regulated alternator from a later 720 truck, late '70s and up 280z/zx, '80 and up 200sx ...they are 50-60 amp output.

 

I've been told that:

 

"With a small amount of modification, you can fit the 90amp alternator off the 1989 Nissan Maxima to the 720. By a small amount of modification I mean change pulleys and drill one threaded hole in the case. I put it on my '82 and have plenty of power all the time"

 

I know the 720 alt will fit where the 620 will, so it should easily fit the B-210 as the idler arm isn't an issue.

 

This is what you need for brighter lights and faster wipers and heater fan speeds. Also if you are, or plan to rum, driving/fog lamps or any stereo amps you will need it.

[banzai510(hainz)]

I believe if a alternator is good you can unplug the volt reg and you should get over 15volts when measuring with a volt meter. If yes your alternator is usually fine.

 

try to find a solid state volt reg.

 

I havent seen a volt reg under volt myself ,usually its the alternator then.

[Pumpkn210]

The Alt over charges when I jump the wire that is the I of the T shaped connector. The Batt light is on when the wire is not jumped. I have been studying my haynes manual and have found that the dead wire goes to the batt light? I have never claimed to be any good at wiring. There is supposedly a fuseable link box somewhere, but I cant find it. Please help. At this point I have the dead wire hooked up on a toggle so to not drain the batt but it is way overcharging!

[slodat]

overcharging will ruin your battery quickly. If you overcharge a battery long enough, at a high enough voltage, it will explode!

[thisismatt]

The Alt over charges when I jump the wire that is the I of the T shaped connector. The Batt light is on when the wire is not jumped. I have been studying my haynes manual and have found that the dead wire goes to the batt light? I have never claimed to be any good at wiring. There is supposedly a fuseable link box somewhere, but I cant find it. Please help. At this point I have the dead wire hooked up on a toggle so to not drain the batt but it is way overcharging!

Um, so is this an internally regulated alternator or not? The battery light being on suggests that the alternator is faulty, or the regulator in this case since you said you swapped the alt.

[Pumpkn210]

It is an internally regulated alt. I thought that it was the alt but I swapped it out with a good one and when the wire is jumped it charges like a mo-fo, so I know it is good. It is my understanding that both of the wires on the T connector should be powered when the car is running. I put the wire on a spare toggle that was already run for the old driving lights. And I turn it on and off so I dont blow the Batt, it was squeaking a little after driving from tac-town. I really need to know where the fuseable links are and where the white/red wire at the alt comes from. Do I gotta tear my dash appart or what? Me Confused!

[thisismatt]

[ggzilla]

It is my understanding that both of the wires on the T connector should be powered when the car is running.

I don't think so. My post above says something about that.

 

 

I really need to know where the fuseable links are and where the white/red wire at the alt comes from.

The fusible link is under hood in the wiring harness by the black box thingy bolted to the side of the strut tower. It doesn't go through the dash or interior. White/red from ALT goes to fusible link and then on to Battery Cable +

[Pumpkn210]

Thanks for all the info! I have yet to fix it cause I have it jumped to a toggle and am using an old crappy batt. But now it makes sence!

[gene knight]

have an issue with upgraded hitachi alternator up to 70 amps in my 521(grimace) with external regulator but it now puts out 17.04 volts at higher rpm, but at idle it goes to 13.46-14.97 volts and have factory voltage regulator so i need help or i also have a 50 amp internally regulator alternator if i use this 1 do i bypass externally voltage regulator? if so which wires do i use from engine bay harness

[ggzilla]

The problem is the regulator. Replace with a new one.

 

To use the Internally Regulated alternator, unplug the voltage regulator and throw it away. The wires to jump depend on whether you have early 521 harness with 4-wire connector or later 521 harness with 6-wire connector.

[gene knight]

i bought a new regulator but it was starting to smoke and this is before i upgraded alternator, so i put old 1 back on and no smoke and things were great but now that i have upgraded alternator i need to know what regulator i should get and for what vehicle. it i go with the internal regulated alternator if i unplug harness which wire to i tap into, cuz i have 6 wire harness plug

[ggzilla]

Yes, new Voltage Regulators are often bad right out of the box.

 

You can use a regulator for a Datsun 521. It doesn't matter which alternator it is, they all are supposed to regulate to 13.5-15.0 volts, which is what a lead-acid battery requires.

[ggzilla]

If you fit IR alternator: after you remove Regulator, on the regulator harness

* Jump W to Y wires

* Jump WR to WB wires

[gene knight]

ggzilla: pm sent

[ggzilla]

Here is wiring diagram out of shop manual.

 

Ignore the wire colors unless you have a 1979 pickup. Instead note the four terminals on the alternator. 1979 Pickup used either LR135 or LR150 alternator.

 

BAT and S are connected on every Datsun wiring diagram I have looked at so far. The factory service manuals show the same in both wiring diagram and schematics.

 

That leaves the L terminal, which goes to the Dash Lamp.

 

If the Regulator harness doesn't have a RW wire, use the RG wire.