robs_seven

iTrader: (1)

Well i have a 79 sa and just upgraded to a 89 alt and i have some info on the swap and i have fixed the external regulator issue. My only thing is i cant figure out if the "L" terminal on the alt goes to the BY in the regulator plug or if it goes to the BY in the engine harness plug. other then that its in the car and wired up i just cant find in the archives where to hook up the "L". thanks for the help
robert

craigw1

aha !

someone with an external regulator as well ! I was beginning to think there weren't anymore left !

ok, PLEASE tell me how u get on. I have yet to start up and check all my gauges and whether the battery does in fact stay charged....but I when wiring up I turned ignition on and got all red lights on the dash and no smoking wires...so far so good.

But this is what I did

firstly, the B terminal is exactly the same...this is the wire that actually charges the battery

I then ran a fused wire from the S terminal to unswitched power

Then for the L terminal I connected it to the white wire with black stripe which is in the mega engine harness plug

here is a schematic of how my system was connected up before

and on the bottom right u can see the white wire with black stripe i connected L terminal to

like i said...i haven't started yet and don't know if it will hold charge and if alt warning light will go out

please keep me posted of your progress. email = cdwhittle@mweb.co.za

robs_seven

iTrader: (1)

here is how i started mine i got this info from gsl-se addict
It worked fine until i put on a new fan and it was under more load and i started seeing problems, then i thought maybe it was wired wrong cause the alt is GOOD, checked out with 15 volts and 80+ amps.

By no means am i saying he is wrong i have a feeling i missunderstood the wiring and got it wrong so im checking where the "L" goes i will look into the wiring you suggested adn let you know

thanks

you hook the newer alts ('89 and later) to a switched 12v instead of a constant 12v, you will get battery drain when the car is off. These guys used a relay to keep that from happening instead of figuring out the cause.

Here is what you need to do:

1. When they say jumper, they mean to connect together with a wire.

2. Unplug and remove the regulator. There should be a connector with 6 wires in it. The wire colors are YL (yellow w/ blue stripe), WB (white w/ black stripe), BLg (black w/ light green stripe), W (white), BY (black w/yellow stripe), WR (white w/red stripe).

3. Connect the YL wire to the BY wire.

4. You won't need to do the other jumper for this alt. You will only need to use the BY wire from the harness.

5. On the '91 alt, you should have a plug on the back with two terminals. The location of the plug depends on if the alt is from a TII car or an NA. My plug is on the back. The NA cars had them on the top. There should be a diagram on the alt that shows which each terminal is. One my car, the one closest to the output post is the 'S' terminal and the other is the 'L' terminal.

6. Connect the 'L' terminal to the BY wire on the harness.

7. Connect the 'S' terminal to a constant 12v. I just connected mine to the alt output post. The 2nd gens ran a separate wire back to the battery. Probably the best way is to do as the 2nd gens did. Get some wire, small is fine (14ga or something), put a fuse inline (2amp or so is probably fine) and connect to battery +. The 'S' terminal is what senses the load and the regulator adjusts the ouput to match. You could also connect to the WR wire on the regulator plug. This would be the same as connecting to the alt output post.

8. Reconnect the large alt output wire. If you use the stock wiring, the connector won't fit over the top post. You can remove the post (there is a circular plastic cover that you take off on the back) and there is a smaller post/nut that you could connect the wire to. The other option is to run a new alt output wire like I did.

That should do it. Get it started and you should be reading 13.8V or so. I know the '79 doesn't have a voltmeter (except when starting), so use a multimeter or an aftermarket voltmeter to check.

This thread may help on the wiring:

https://www.rx7club.com/1st-gen-archive-71/electrical-2nd-gen-alt-1st-gen-388262/

The only thing I see is that this jumper stuff will keep the choke relay from working. Are you still using the stock electric choke or do you have something different?

craigw1

nope....i've fitted a weber 48 ida so have removed the choke and the start assist.

re your guide...thanks...very similar to what i've done....except i see we are just needing confirmation on where the L goes. the B is simple...that is exactly the same. The S is simple...that is a fused new line to a constant source of 12 V.
NOW WE JUST NEED TO DAMN FIGURE THE L !

you can see my first problem....my 6 wires at the regulator are coloured as follows :

grey -> from A terminal on my ALT
green -> from F terminal on my ALT
blue with red stripe -> from N terminal on my ALT
black with white stripe-> from E terminal on my alt

the other two wires in the 6 point plug at regulator are :

white
black with yellow stripe

these two then go to a t-plug (as in my diagram)
the t-plug then goes to the harness plug as in the diagram

as you can see, none of your colours tie up with mine.

question for you : what are the 4 colours of the wires that go from your old alt to your old ext regulator ?

then also please tell me where the other 2 wires from your 6 point alt plug go to

thanks

c

robs_seven

iTrader: (1)

My colors match his discription perfect, the plug has

YL yellow blue stripe
WB white black stripe
Blg Black light green stripe
W white
BY black yellow stripe
WR white red stripe

i just put a jumper across the YL and BY

then the others are just open in the plug. my ? is in his instructions it says connect the L to the BY in the harness, now is that the engine harness or what???? so i dont know what to do with it. Wacky racer pmed me and said that the "L" could be left off and you just lose the voltmeter in the dash. not sure yet have not tried it. ill let you know

craigw1

ok, i've managed to tie up some of your colours to alt terminals as follows :

your black with yellow strip = N terminal
your white = E terminal
your white with black stripe = F terminal
your white with red strip = A terminal

so at least now we have agreed 4 of our terminals and therefore 4 of our 4 wires

I can see where you having a problem

the way I think he meant was as follows :

do point (3) ie connect the YL on the regulator 6 point plug to the BY wire ie the wire which used to go to the N terminal of the alt

now connect the L terminal on your new alt to this wire (BY)

because eventually if you follow that YL wire from the 6 point old regulator plug it does find its way to the big black harness plug

(effectively what he is saying is run a wire from your L on new alt to the YL wire which goes into the 6 point regulator plug)

I can't see him trying to explain it any other way because then why would he have inserted step (3) ?

robs_seven

iTrader: (1)

what about the jumper he said connect witha wire the two YL and BY. so why put the L on the plug should it go to the engine harness alone?

craigw1

sorry for confusion...maybe not explaining myself properly

I said that he must have meant you must join the L from your new alt to the BY that he just 'jumped' to the YL in step 3

because

if you just joined your L to a BY on the engine harness plug, then why did he mention step 3 at all ?

he basically just inserted a third step...you could just have gone straight from the L terminal to the YL.....instead he said join the YL to the BY and then go from the L to the BY.....so in your case you never have to touch the engine harness plug at all

robs_seven

iTrader: (1)

i just hooked it up with the instructions with wackyracer about leaving the L untouched. it works fine the tach works and the lights dont come on and the voltmeter doesnt work. not that huge of a problem because i hav mech guages for that stuff. and the dumby lights are junk any ways. im going to test drive it and iwll let you know.

craigw1

good luck, keep me posted as to whether you hold charge, etc

i think whats happened in my case is that the car was worked on some time before and hence all these change in wire colours. The shiny new regulator is just a dead give-away

craigw1

so what happened ????

robs_seven

iTrader: (1)

i had the battery checked and it seemed good and then i hooked it up alldifferent ways, i cant get more then 11volts and it dies all the time, no matter what, there is not enough juice to get a good spark and support everything else it sucks

Phiber Optik

iTrader: (2)

doesn't the 89 alternator have a built in reg? (all the ones i have seen do) so why are you trying to hookup the external reg then?

robs_seven

iTrader: (1)

with the external regulator on the 79 you have to jumper it so you get power back to the relays, if not none of the dash lights work. i dont have the actuall external reg in the car just using the plug.

dean23

sorry to ask such a basic q on this thread.. but wat effect does an upgraded alt give?

85 FB

Alternators give out power, most commonly known output is amps. 1st Gen alternators are extremely wimpy. Upgrading alternators allows more amperage to power the electrical accessories and components in the car: headlights, A/C, heater, lights, etc.

I upgraded mine (check out the pinned article in the archives) and have never been happier. Lights don't dim anymore when I give the system a full load (all lights on, heater on), even when having the turn signal on.

dean23

sound good. what would a good uprgrade be for me to get? i dont really know too much about this kinda stuff so i might as well ask. :]

craigw1

upgraded alts are rated for higher amps. For example the std 12A first gen alt was 50A. the gsl-se had 60A. the second gen has 70A-80A, depending which model

but basically the higher the ampage the more current it can take. so for example. say u driving around at night with your old 50A alt, lights are on, radio is on, etc....and then u try and wind the windows down, it'll go a little slower and you might even see your dash lights fade a little. Put in that 80A amp alt and those windows will fly down !

hope that gives you some idea

fcdrifter13

I am a fan of a GM alt swap.

craigw1

in other news, after my first startup last night, the dash light went off for the alt light....so it looks as if it is wire up properly. I'll just have to see if I hold charge. On the other hand I got a crap reading on my oil pressure gauge...it just went right across...hopefully that has nothing to do with the way i wired up the alt but rather a faulty oil pressure sender. I will be replaing the sender today. If I get the reading to work I can then finally cover up all those wires nicely.

question : The temp gauge gets its reading from below the oil pressure sender. What then is the connector for at the thermostat housing ? Is that one just to show that if there is no water then the dash light will come on ? I haven't connect this one up.

Is it possible that somehow the circuit needs to be complete so that I need to connect this thermostat housing sensor up and then might get readingon my oil pressure gauge as well ? or am i grabbing at straws here ?