The anti start "relay" is a small module that has a transistor and timer chip in it it controls the start relay itself on the control side....wiring is as follows:
Blue/white is power in it should be constant when cranking..
Black/white is power in from the ignition switch to the transistor this gets sent to the start relay when starting....it gets sent to the start relay on a white/black wire to the control side of the start relay....last wire is the ground....power comes into the timer chip on the blue/white wire and then to the transistor this turns on the transistor to allow power flow from the ignition switch to the start relay


This relay/module dosent have anything to do with the ignition circuit it only controls the start relay and inhibits restart thru the timer chip

That makes sense, the circuit would be closed under normal battery only power, and with the alternator turning, the power supply would be above 13v and the circuit opens. Assuming the white wire is the anti-start relay, if I were to use a generic ignition switch, I would have to wire it to the ignition relay terminal (hot in run AND start position), or I could just leave it unconnected and lose the functionality, but not lose starting ability.

As to the previous post, I am aware of the mechanical anti-restart setup on some trucks, but this is an electrical module. Not sure on the true vintage of my truck, the parts guy told me late 80's.

My take on how that works: The anti restart is a 4 terminal relay, pos and neg, and a switched circuit. The relay is normally closed when no power is going to it. It is in the start circuit along with the key switch, neutral switch, and starter relay. The anti start relay only operates when the voltage going to it gets above approx. 13 volts. Key on, white wire (although it may be black/red wire) should be energized and everything should be getting power, anti start relay, dash, ignition, lights. Since the voltage is below 13 the relay has the start circuit still closed and ready to go. Turn key and start engine, voltage rises above 13 and relay coil has enough power now to pull the contacts open and making the start circuit inoperable. The coil in the anti start relay stays energized the whole time the motor is running and voltage is above 13.

well as far as i know unless they have incorporated an electrical circuit in addition... the anti-restart is usually limited to the keyswitch.

It is a mechanical lock inside the keyswitch that is activated when the key is turned to the start position and only unlocks when the key is turned back to the off position.
So in effect...
when you go from 'off' to 'run' and then from 'run' to 'start' position the lock goes in place so when you go back to 'run' position it prevents you from turning the key back to the 'start' position.
The only way that is released so you can turn it back to 'start' position is to turn the key to the 'off' position, the internal lock is then reset so the key can be turned back to the 'start' position during the next starting sequence.

Now if by chance there is an electrical module that controls anti start that would only be active while the engine is running i would think. So... if the engine is not running you would most likely see the circuit inactive.
I would have to have the manual to be certain but that seems like the logical way it might work in my opinion. Based on the model and serial number of the truck you mentioned the anti start modules (electrical) were not being used back then, at least not that i can remember. :o)

Can anyone confirm if the anti-start circuit is suppose to get power at start only or at run and start?

There is a local starter rebuild shop, I will see what they can do before I buy the auto starter. In looking at the pictures online, the nose cone does look like it might be 1/4" longer for the automotive application.

you can try the automotive starter but in alot of cases they just won't work.
things you need to pay close attention to are the nose piece, the bendix gear teeth. You verified on the site info the bendix teeth count is correct but you still need to double check that when you physically see the automotive starter. The nose piece is the other thing... make sure it is positioned in the same position and also make sure the part that fits into the bellhousing that holds it in place inside the hole it fits in are the same size and also look closely at the nosepiece shape and thickness.
In alot of cases an automotive starter may look like it will work until you run into any one of those things i mentioned above.

So basically you would have to take the old starter with you when you go to purchase the automotive one and insure everything is a match.

Do you have a starter rebuild shop anywhere near you?
Most of the time they have those starters already on the shelf rebuilt and you can go swap it out. The cost of a rebuilt one isn't too bad compared to a new one.

One additional question, can anyone confirm if the automotive starter for this motor will work? I see that they have different part numbers, but I have looked at several pictures online, and the starters for the pre-82 B2000 Mazda trucks have the same appearance, 8T gear, CW rotation, and obviously they are 12v setup, but they cost 1/3 as much as the forklift PN?

I went back with the multi-meter to double check everything again, and here is what I found:
I only have 12v at the coil when cranking, so my new ignition switch is bad.
Wire breakdown at the switch
Blue is Pos. from battery
White Wire goes to anti-restart
White/black wire goes to the start relay
Black/Red wire goes to ignition coil.

When cranking all 3 pins are energized, when in run position, the batt. supply voltage is not going to any of the 3 pins. I am going to try a generic ignition switch as soon as I get a new starter.

Can someone confirm what is suppose to happen with the anti-restart wire, is it only energized when in the 'start' position? Do I need to hook this up at all?

Also, the electrically controlled plunger on the carb, is the a fuel cut off solenoid?

Thanks to everyone for the help, I will update when my new starter arrives, I tried a rebuild today, but the armature half disintegrated, not sure if that was 100% me, or if it was on its way out anyway, nothing quite like starting in the middle of someone elses failed attempts to repair something!

There are no melted wires at the connector for the ignition switch
The connector is a 4 pin block, with 4 female spade pin connectors.
-all white wire
-black with red stripe
-all medium blue wire
-white with black stripe wire.

The carb does have 1 wire going to it, it is connected to a plunger that I assumed was used to verify fuel pressure, the lead runs to a 2 in 1 connector that runs from the positive side of the ignition ballast resistor, and connects with this plunger and a lead from the distributor.

I would make sure it is in fact the spark that is the problem. Can you pull the coil wire away from the coil enough to watch it spark and what happens as you let go of the key and it shuts down? I'm not familiar with that gas carb but if there is wires going to it, it may have some kind of a solenoid that shuts down the main jet. Maybe check to see if that stays energized.

whats the connector on the back of the keyswitch (on the harness) look like? melted ANY at all? look for any malformed plastic around it...
how many wires are going to the ignition connection on the keyswitch? check those and make sure there are no broken or melted wires there.

There is 11+ volts at the coil when the key is in the run and the start position.

The connection at the key switch can be installed in two directions, but the engine only turns in one orientation.

I checked the ballast resistor and it is intact, 0.2ohm of resistance, I also tried to bypass the ballast with a jumper wire with no change.

Is there 11+ volts at the coil with the key switch on but not turning it to start ? If not, is the plug that goes into the back of the key switch on properly and not backwards ? If that's ok then check the ballast resistor mounted on the side of the ignition coil. Anti-restart is supposed to prevent the starter from working if the engine is already running.

I pushed my troubleshooting a bit too far (I think I cooked the starter motor), I held the key for 5-10 secs. after the engine started, the engine is definitely running and responsive to the throttle, but once I release the key from the start position it dies.
Does anyone have a schematic for the ignition switch?

While digging around under the dash I found a box, slightly larger than a relay labeled "controller anti-restart" can anyone elaborate on what this does?