Mazda B3 Distributor Wiring Diagram
Pasty Luckenbaugh
The A14/A15 electronic distributor has a positive wire and a negative wire that goes to the black box on the distributor. The positive one is a White/Red strip and the negative is a White wire. The positive wire connects to the position that is marked "B" on the box. The negative is connected the the position that is mark "C".
The Z24 Distributor has (4) wires that go to it but it is also an (8) spark plug distributor. The Blue wire connect to "E". The Black/Yellow strip connects to "B". The White wire connects to "C" and the Red wire connects to (I). I am only going to use the primary plugs at this time so if it is as easy as it seems, I would only have to connect straight up to "B" and "C".
On the dizzy...one wire is to ignition power, the other two go to the two coil - terminals, the 4th wite is for shutting the exhaust plugs off under heavy throttle. That's about it. Will post when I get home.
Not sure what you are planning or how you plan to use this distributor but with power on the Black/White wire and engine turning over, will cause both the Red and the Blue wire to turn on and off to fire the coils. If using just one, either will do there's no difference between them. For a Z24 motor, it will run best when both coils are working.
If I run both coils, does that mean I need another MSD spark box for exhaust coil as well or can the exhaust plugs just run straight off the coil with the intak plugs running on the spark box? I thought the exhaust plugs were only for emissions.
You can get a second MSG if you want or can afford it but the stock coil will work just as good. If you run one only you can connect to either the intake or the exhaust side, won't matter a bit, and use a stock coil on the other.
The exhaust side plugs for emissions is a myth. Both plugs fire together to give two ignition sources which shortens the burn time and requires less ignition advance. Nissan's intent was that this set up will allow more EGR to be used to control emissions but luckily it also is good for mileage and efficiency.
The white wire??? It's part of a system that can tell the distributor to revert back to single plug operation to reduce engine noise when passing or climbing a hill. A vacuum switch grounds the white wire and the distributor turns off the exhaust side plugs, but it also advances the timing to compensate for the longer burn time of a single plug. When power is reduced the switch opens and the distributor changes back to dual plug and retards the ignition.
The coils have 12 volts on them at all times the ignition is on. The distributor's job is to make and break a ground connection on the other side of the coil to complete the circuit. Hard to explain but once you see how it works it make sense.
If this is true, where do I connect the negative wire that comes of my MSD spark box. Direction state to connect it to the negative side of the coil. This where I had it on the A15 coil. Just want to make sure I don't mess anything up.
I scavenged a pigtail from a KA24DE Altima that fits but the wire colors may be different from a 240sx. The Altima has Black, Orange, Yellow and Blue. For the Altima I have confirmed that Black is Ground and Orange is 12 volts. Other 2 wires, I'm not sure and am not sure if the 4 positions are the same for both cars.
I don't think you can run the KA distributor... it's actually a crank angle sensor (CAS). Nothing about it will work without the KA ecu and sensors to set the spark and timing with it. Inside the CAS is a wheel with 360 marks and 4 larger ones. A photo cell 'reads' the dots and marks and sends this to the ECU so that it knows exactly where the crank is to the degree.
You will need a dizzy from a 4 plug motor like a L series matchbox or a points dizzy. Or an 8 plug dizzy from a Z24 and leave 4 wires off.
Maybe this helps... -carbd-ka/
Something else to through out there for z24 ignition. If running only one side the exhaust plugs are in a better position in the head. The mini truck class at my local dirt track are only aloud to run 4 plugs and they claim it runs better on the exhaust side plugs. I guess its due to the plug being in front of the intake valve. andI believe if running an msd box you can run off of the intake signal from the dizzy and from the msd split it to both coils.
The motor runs best with dual plug. If for some reason you have to run single plug he says the running the exhaust side is best. You would also have to run way more advance with single plug. As far as I'm concerned I've yet to be convinced the MSG is better than the stock EI system. Lots of talk but no numbers.
I've seen msd make a difference, but that was a 94 Chevy truck, stock is junk in those and his whole system was msd except plugs. Saw that thing still run with the button that connects the cap to the rotor completely melted out.
Thanks for your help this forum is exactly what I needed. Ihave an 85 720 with a carburated z24 engine. Ever since I bought it, I've had electrical issues and it's because the previous owners just cut and twisted wires together all over the place. That, combined with the fact that a lot of the wiring insulation is disintegrating, I decided to rip out all the wiring and replace it with my own circuits. The distributor was the only one I was concerned about getting right since the rest are pretty straight forward. I will try this and report back how it goes. Thanks a ton!
This should be the later Z24 distributor. The 4th wire is white or maybe gray and on it's own plug. The whit wire is for causing the distributor to shut down the exhaust side plugs. If used on an earlier 3 wire just leave disconnected.
I'm experiencing distributor troubles along these lines also. I'm running a z24 in my 320, it's an '89 engine with an '86 distributor. I have a Hyfire 6a on the intake side . I found today I am only getting spark on the exhaust side, figured the Hyfire had dumped, even though it still triggers my tachometer. I disconnected it, running straight from the distributor. Still no spark. Maybe bad coil...nope, the exhaust side triggers the intake coil just fine, the intake triggers neither side. I now think the module in the distributor is bad. Wondering, could the Hyfire caused it to go out? Right now I'm running the intake plugs with the exhaust side trigger.
One of the big problems people have with their Mazda Truck is timing. Many people will buy a truck that someone has fooled with before and since a lot of times they have never owned a mazda before they can't get it timed right or they decide to change the belt and can't get it right again. This is a real quick procedure to check your timing and can also be used to pinpoint other problems in the engine without a bunch of instruments and gauges.
Ok, first off this article is based off of a Mazda B2200, this procedure should be universal with all distributor vehicles but timing marks and things like that will vary slightly between different truck models.
You will need to remove the upper timing cover so you can see the cam sprocket. It will come off with 4 10mm bolts, 2 on top 2 on the bottom. My engine is fairly stripped of accessories so this takes me about 47 seconds but you may have to work around emission ducting to the exhaust and stuff like that.
If the timing mark on the harmonic balancer is lined up, #1 piston at TDC, and the cam is installed properly then #1 cylinder should be on its compression stroke. To double check this turn the engine over by hand with your thumb over #1 spark plug hole, as the timing mark reaches TDC AND #1 (A) on the cam sprocket lines up you should feel pressure push your thumb off the hole. Also if you remove the valve cover both valves on #1 should be fully closed and the springs uncompressed.
Now to check the distributor. It should look something like the picture below, where each wire goes depends on the firing order of your engine. On the 88-93 B2200 it is 1-3-4-2 with 1 being the cylinder at the front of the truck. So just take the 2 screws off for the distributor cap to look where the rotor button is.
Here is the rotor button:
The contact on the rotor button (by the #1 in picture above) should be located where number one spark plug wire would be on the distributor. If that is where it is at it should be installed properly if it is some place else take the distributor out and line up the dimple on the gear with the mark on the distributor shaft and put it back in. Note that the distributor must be installed with the cam properly installed and all timing marks lined up.
The arrow indicates the rotor button is going to rotate clockwise as it rotates it moves past each point on the distributor cap which completes the circuit from the ignition coil to whatever plug it contacts and you get spark.
This procedure can tell you other things as well. For instance in this picture you can clearly see my rotor button is fried and so my distributor cap probably looks about the same on the inside (and it does). This will cause any number of problems from not starting to rough idling, misfires, poor fuel mileage, and lack of power. Also if you see a lot of corrosion or black carbon build up on only one contact there is a problem with that plug or cylinder somewhere as it is requiring more power to fire. Also while your turning the engine if it doesn't get hard to turn as the button goes past where it would make contact with one of the points then you have poor compression in the cylinder it just passed and you should do a compression check. Of course then you know that either the rings in that cylinder are bad or there is a valve train problem. Just one of the many tricks to engine diagnosis.