craigw1

am swapping alt from second gen series 4 tii into first gen.

first gen alt plug has 4 coloured wires :

black with white stripe
blue with red stripe
green
grey

tii alt has two wires :

white
yellow

i have seen a great diagram posted elsewhere about this swop...but the colours don't tie up. (see attachment)

so chaps....which wires go where ?

3rd and final 7

iTrader: (9)

http://www.rx7.org/public/altxref.html here chk this page out. you ll need to find out if you have an LS or a LR alt , its all on the page and it will help you wire it all up. i hope it works out for ya!

craigw1

ok, so that diagram that i attached was wrong then ?

according to your link the first gen has a LR charging system and the tii alt comes from a Ls system

hence its not as simple as just changing the plugs ?

anyone else done this swop ?

i'd prefer using the smaller 80A alt rather than the bigger 50A one from my 12A

John64

2nd Gen alternators need to see a constant source of power I believe (been a long time since I did my swap) White black to white black white green to power

craigw1

sorry...made a GRAVE error at the top there

its a SERIES 5 alt i am swapping in not a series 4

apparently series 4 isLR system (same as first gen)

the series 5 one i want to put in is apparently the LS system

now i've figured that the white wire (on the right hand side) of the plug is the L terminal and the yellow wire (on the left hand side of the plug) is the S terminal

but can someone please tell me what the wires are for in my first gen ?
like i said the alt has 4 wires on the plug going in

black with white strip
blue with red stripe
green
grey

so what do i do now ???

I know that the L will remain....so which of my four must I wire up to the white wire of the tii alt plug ?

then I must take from an always on source....i will take direct from the battery...and fuse it with a 30A fuse...and connect to yellow wire (S terminal on tii alt)

has anyone not ever done this mod yet ?

i've read loads of posts of guys doing the mod but (1) the wire colours are different and (2) they end up with problems of the battery running flat

gsl-se addict

iTrader: (3)

The alt that you have now sounds like a '79. It is an external regulator alt. So first, you need to adapt the wiring so the alt is like an internally regulated alt. There is a thread in the archive called "83 alt in a '79" or something like that. That should tell you how to bypass the external regulator and such.

Once that is done, the L terminal goes to the alt warning light. You need constant 12v to the S terminal. I would probably use smaller than a 30A fuse for the S terminal. It only draws like 1A normally. I would probably try a slo-blo 2amp or a fast-blo 5amp. There is a thread in the 1st gen archive that tells about an S5 alt conversion with the correct wiring (S terminal to constant 12v). The one in the diagram you posted is incorrect and will lead to battery drain.

Good luck with it. If you run into any problems, I can help. The S5 alt is a nice upgrade. The battery voltage is much more constant now.

Kent

craigw1

ok, i will use lower than 30A on S terminal on tii alt (yellow wire on tii alt plug)

but can someone tell me which of the 4 of the first gen alt plug needs to go to the L terminal (white wire on tii alt plug)

4 to choose from

black/white
blue/red
green
grey

craigw1

hey guys please help me out here. i've done loads of research but come up with the battery going flat problem and all sorts of different colour coding.

anyway, the pic i've attached is the plug which goes into the s5 tii alt

it has a yellow wire and a white wire

now i've figured that the yellow one is the S terminal. This i am going to connect up direct with a fuse to a constant power source. Thats the easy part.

Now for the white wire. WHERE DOES THIS GO ?

I have 4 wires which was on the plug of my first gen alt

one of them must hook up to the white wire

the 4 colours are :

black with white stripe
blue with red stripe
green
grey

so which one is it ?

John64

Not sure how to help. As stated above you have an external regular by the sound of it. I gave you the connections for the one i did.

gsl-se addict

iTrader: (3)

It appears that the wire colors in the old plug are different than North American cars. In the US Spec '79 cars (only year to have external regulated alt in US) had a 4 terminal plug, but only used 3 wires (W, WB, BY). I am not sure how much we can help without the proper wiring diagram.

You may not even need that plug at all. Track down the external regulator. Maybe some pics will help. The US spec has:

- WR (power)
- BY (from alt)
- W (ground/alt)
- BLg (12v switched)
- WB (alt)
- YL (to choke/check relay, for alt dash warning light)

Once we know the wire that goes to the choke & check relay, that can be connected to the L terminal on the alt. The alt will work without this wire connected, but the dash warning lights will remain on. Hope this helps.

Kent

Edit: Are you sure the yellow is the S terminal? From the above diagram, it appears to be the L terminal. WB is normally the L terminal. The BW is for the R terminal (switched 12v).

craigw1

ok, starting to make sense now...appears that mazda have beem buggering around with wire colours...thats why i'm not making sense to you guys. Also, we now find out that you only had one year model (79) is the US with external regulator.

Ok, I assume that since I have a 4 point plug that I must have an external regulator as well. Obviously this will no longer be needed as the s5 alt has internal regulator

ok, but lets try the question this way then.

For those of you with 79 alt or have done the swop...of the 4 connectors in the plug, which one is the L terminal ?

is it :

top left
top right
bottom left
bottom right ?

I'm hoping here mazda just buggered the wire colouring but not the actual sequence on the actual alt itself. for example. if top left is L then so be it..I will hook that one up to the white wire on tii alt plug

can't believe one damn wire is holding my install up

i will try and post a pic of my alt so you guys can see the plug and the wires

gsl-se addict

iTrader: (3)

Well, the '79 alt doesn't go to the alt warning (L) directly. The wires go to the external regulator and then the choke/check relay. The choke/check then controls the alt warning light. I think the best option is to track down the external regulator. One of its wires goes to the choke/check. We can either do this by process of elimination (we know which colors go to the alt, we can figure out the choke/check connection from the remaining few) or you can try to trace the wires between the choke&check and the external regulator. The choke&check relay is located on the inner fender on the US drivers side (Left). I think it is in the same position for RHD cars. It is a big relay with 2 plugs, normally. It usually has printed on the top "Choke Check" or something similar.

craigw1

ok, so more complications now

which leads to the next question

does the tii alt need to be wired to the warning light directly or must it go via the choke/check ?

craigw1

ok, i think i have finally cracked it !

as u have seen, my tii alt switch has two wires

yellow - this is the S terminal

here i am going to connect direct to the battery. was thinking of 30A fuse but advised here to go with 5A instead....so will go with 5A

white - this is the L terminal

this needs to go direct to the alternator warning light. and i find this wire as the YL ie yellow with blue stripe going into the regulator

so...tomorrow night i will go and look for this yellow wire with blue stripe and disconnect it from the regulator and connect it to the white wire on the tii alt plug

the choke relay does not come into this thing at all. in fact....as i will be running a 48ida i will be disconnecting and removing the choke cable and related parts plus the hot start motor and cable that went with it.

WISH ME LUCK !

craigw1

well....it appears my regulator must have been changed at some point. The wire colours just don't tie up.

so i did the following : I removed the regulator and the whole cable with the 4 wire plug to the alt.

I then ran a line with 10A fuse from the yellow wire (S terminal) to power line.
The L terminal I just guessed and ran it to the white wire

I hooked up the battery...turned the ignition key....and I got a reading on the voltmeter...and i got all the red lights on.

at least thats a start....when i finally start I will need the lights to go out to ensure i've wired it up correctly.

oh....and for some odd reason the oil pressure gauge just went all the way to the right hand side. Anyone know the reason for that ? Where exactly is the oil pressure sender unit ?

gsl-se addict

iTrader: (3)

The oil pressure sender is a brass mushroom looking thing on the left side of the engine (below the oil filter)

gmanuser

email me my email is glenn_mesa@hotmail.com this guy name mario sent me a how to with step by step procedures when i needed o find out how to do it they are some big pics that i cant post on here email me and i will foward it to you you can ask him any questions if you need he is a guenisss with it and yes it does requruie a constant battery source so dont leave it for a week without driving it or it will kill your battery if you leave it oer a weekend you might be alright.

craigw1

i just figured why i got crap reading on oil pressure gauge

its because the gauge also gets voltage from the regulator

damn...this alt upgrade is becoming more complicated....

now i got to figure how to get regulated volts to the oil pressure sender !

craigw1

Just following on from my previous posts, i've attached a simple schematic of the alternator wiring that was present when I had the 12A in

as you can see, four wires come from the alt. On the Alt itself there were four letters ; E, F, N, A. I have no idea what these letters mean. the four wires go from there to the regulator. from the regulator 2 wires come out which go to a t-plug. the t-plug then joins to a mega fat plug.

in terms of wiring up the s5 alt.....B terminal exactly the same ; ran fused wire from S terminal to unswitched power. the only one i didn't know was the L terminal which must go to the dash light. I took a flyer here and connected it to the white wire with black stripe which goes to the mega fat plug or is the vertical clip in the t-connector in my drawing.

as i said i connected up the battery and turned on ignition. all dash lights came on and there was no smoking wires ! but like i said, the proof will be in the pudding when i eventually start up and the alt light goes out on dash and battery doesn't run flat after 2 days

can anyone see anything i've done blatantly wrong here ?

i've also been to the website http://www.rx7.org/public/altxref.html
but for some reason my alt setup as in my drawing is not listed there. all the alt pics there are with 2 point plugs...mine is a 4 point plug. I guess it ties up with the US '79 model which had an external regulator ?

craigw1

any SA's with external regulator done this mod successfully ?