Zaphod

Hi, as the title states... what else is needed (the alternator of course) to swap an NA alternator into an NB? If I go standalone I need the NA alternator or Jasons circuit or Abes mod. I want to compare what's the easiest way... (too many other difficult threads at the moment... engine rebuild)

Thanks

P.S.: I used the search but there were like 369 topics. I get the feeling lately anyway, that there is something wrong with the search engine... A lot of results no matter how many search words etc.

Greets

Zaphod

I have to push this up - can't someone give me a hint?

Are the belts different between NA and NB? Are the connectors the same?

Thanks!

supra441979

iTrader: (10)

NA/NB Compatibility Guide Looks like NB alternator fit NA, but no sure about NA alternator fitting NB.

Rafa

iTrader: (22)

Send Ben a pm. I think he was the one that posted some info on that subject.

Zaphod

Thanks Rafa, I sent a PM.

I just had a look at ebay.de and found this:

Lichtmaschine Regler Mazda 121 323 626 MX-5 MX-6 Xedos bei eBay.de: Autoelektrik (endet 21.05.09 12:14:43 MESZ)

It's a regulator for the Miata alternator. If you have a look at the list, they say it's for the 94-97 Miata(MX-5) AND the 98-00 Miata(MX-5)... WTF I thought the NAs were internally regulated and the NBs were regulated via the OEM ECU...?

Greets

hustler

iTrader: (6)

you can either notch the 1.6 bracket (grinder or circular saw) or use the standard 1.8 bracket without modification. 1.6 is a v-belt, 1.8 is ribbed.

I have a 1.8 alternator with a 1.6 bracket and may need to switch to a smaller belt if it stretches any further.

samnavy

iTrader: (7)

So, it's a direct swap then?
Remove the NB alternator (leave bracket installed to block).
Install NA alternator and connect wires?

The pulleys should be able to grip a ribbed or v-belt, right?

I understand using the NA alternator in an NB for Megasquirt parallel installs due to something about the Megasquirt not being able to control the NB alternator output voltage... and the NA alternator is self-regulating?

If I'm right about the above, are the electrical connections the same for both alternators? The NB harness should have an extra wire or 2 on it?

harleybutter

iTrader: (34)

I thought the NB harness for the alternator was slightly different... Maybe my memory sucks?

Zaphod

O.K. just had a look at I.L.Motorsport-

Alternator Belt NA 1,9 + NB all genuine

1,9 NA and all NB (1,6 for Europe & 1,9) have the same belts.
Bracket for all 1,9 NA and all NB is equal.

More information:

Connectors:
NA 1,9 connector



NB Connector



O.K. something about the regulators:

As I wrote, I found these regulators at ebay:

Here it say's it's for NA 1,9 and NB but I suppose this is a mistake and its only for the NBs.

Lichtmaschine Regler Mazda 121 323 626 MX-5 MX-6 Xedos bei eBay.de: Autoelektrik (endet 21.05.09 12:14:43 MESZ)



This one is for NA 1,6 and 1,8:

Lichtmaschine Regler Ford Probe Mazda 323 Kia Sephia bei eBay.de: Autoelektrik (endet 26.05.09 12:54:57 MESZ)



If I have a look at the pics, the only diffenrece is the little pin at the right marked B+

Maybe I could just swap the regulators?

As I am this far - I just keep on collecting information.

Alternator circuit for NA:
(excuse the German definitions, Lichtmaschine means Alternator or Generator)



Alternator circuit for NB
(again, excuse the German definitions, but I think Generator is international)



Can someone explain? The NB alternator is not connected to ground anywhere?

The W/B line at the NA diagramm goes directly to the warning light at the gauges.

Both NB lines go to the ECU (PCM) - the warning light is switched from the ECU.

Greets

Saml01

iTrader: (9)

I think you need to do something to the NA alternator, some sort of circuit needs to be added. I think Cjernigan knows because I think his car has a NA alternator but is an NB.

boileralum

iTrader: (8)

If you add an older alternator w/ built in regulator, I think it will be fine. The added circuit with MS is due to the stock ECU regulating the alternator on the NB. I think as long as you take care of the mechanical alignment (pulley and tensioner bracket), you will be fine.

Joe Perez

iTrader: (8)

The NB alternator, like most alternators, is connected to ground through its housing.

The wiring and connectors are indeed different, however not impossible to change. The best thing to do would be to obtain the pigtail (connector with leads attached) from an NA, and splice this into your car's wiring.

On the NA alternator, you have the large screw terminal which connects to the heavy wire feeding the main fuse. This will interchange directly with the NB's wiring harness.

The NA alternator has a flat terminal which expects to see +12 all the time. On the NA, this is white / green wire, which comes from the 30A INJ fuse. It is not switched.

Then, the NA alternator has a second flat terminal which provides a closure to ground to illuminate the light in the instrument cluster. On the NB car, the light in the instrument cluster is driven by the ECU, a brown/red wire. You'd need to extend this wire to the alternator.

All in all, it would likely be much easier to build Jason's circuit to control the NB alternator.

demetri

iTrader: (2)

i'm running an NA alt in my NB. NB alt needs the reg in the ecu. NA alt has reg in it. as Mr Perez said. i tried to build Jason's circuit but I suck at electronics so it didnt work. i ended up building a relay circuit so the regulator doesnt stay 'on' and drain the battery (i think, it was a couple of yrs ago).

JasonC SBB

Caution:

In my FSM the wire colors of the Field and Warning light were reversed as compared to my 2000.
I don't know which particular FSM's have it wrong.

demetri

iTrader: (2)

damn wire painting people!

miatamike203

I know this is an old post but I just installed a 96NA ALT into a 99NB and the only thing that needs to be done is run a wire from the ALT to the dash as said above for the batt light. So other then that it was all plug and play.