240z electronic ignition help

[Mikez31ss]

Again I'm going to post withing your quoted post for simplicity sake.

 

 

Thanks for the pictures! Just saw that you have a '73 240Z, based on the John Hull charts you were using i was assuming you had a '70-'72 Z.

 

Yep it's a '73. The John Hull diagrams were available and easy to modify. Sorry for any confusion.

 

1. You might have used an incompatible measuring mode on your multimeter. Try this, connect the black wire to the middle COM socket and then set the mode switch to "Ω 2.0K" (two positions clockwise from the setting in the photo). What resistance do you get in this mode when measuring the pickup coil?

 

I've tried both ways. The way the meter dial is set up, the ext settings just seemed best. I get more consistent readings there. I'll try to get you some readings from both modes.

 

2. Your wiring looks correct on the photos! It would be good to have another look at the +12V (b/w wire) supply, as everything else looks good. You have posted that you have 12 volts on B, could you also measure the voltage between B and ground while cranking?

 

The 12v wire on the coil pos is what is referred to as the "longer black/white" wire in writeups. I'll try to get that measurement but the meter only has probes, no alligator clips, and I'm working alone so the distance between the key and the coil limits what I can do. I can prolly rig something up.

 

3. Could you try to do a photo of the backside of the tacho while it is still installed? (No need to remove it) Would like to find out if its the three or four wire type, that will help in the wire identification

 

A photo of the rear of the tach while it's still installed? I don't see how I can do that.

 

P.s. from what i see in the '73 manual, the original wires would be like this:

Black/White #1: +12V from ignition switch to ballast resistor (currently connected as +12V supply to coil(+)/HEI module)

Green/White: from ballast resistor to four wire tacho (disconnected)

Black/White #2: from four wire tacho to coil (+) (disconnected)

Black: from distributor/breaker points to coil (-) (disconnected)

Black/Yellow: to throttle opener vacuum control solenoid (disconnected, solenoid missing in your car?)

Green: no idea yet

 

You know... I've just realized there is a wiring diagram in BE of my downloaded FSM with wire colors marked. I wondered where you were getting those. I appreciate you looking those up for me and I apologize that I didn't find the diagrams myself. Gives the appearance that I'm asking you to do things I should be doing myself. Sorry.

I don't see green in the FSM but I assume it's for the noise suppressing resistor.

The black/yellow wire is snipped and was taped off. I don't see anything that looks like a throttle opener solenoid. I'd guess that was used with the original SU carbs. My car has Weber DCOE18 carbs.

As I understand it, I have everything I need for spark. But just for info, the black/white #2 you mentioned above would have voltage in a factory configuration, right? And my tach doesn't work. I don't know that this has any bearing on why I'm not getting spark but since I'm not getting spark and everything we've discussed says I should be I'm just thinking of what-ifs. Grasping at straws I guess

On second look I see one of the black/white wires comes from the tach and the other comes from the ignition switch.

Also I have 3 black/white wires. I'm guessing the other was for the throttle opener relay?

[vantage]

As I understand it, I have everything I need for spark. But just for info, the black/white #2 you mentioned above would have voltage in a factory configuration, right? And my tach doesn't work. I don't know that this has any bearing on why I'm not getting spark but since I'm not getting spark and everything we've discussed says I should be I'm just thinking of what-ifs. Grasping at straws I guess

On second look I see one of the black/white wires comes from the tach and the other comes from the ignition switch.

Also I have 3 black/white wires. I'm guessing the other was for the throttle opener relay?

 

The third b/w wire would be the voltage feed for the throttle opener relay, correct. I am not sure about the tach in the wiring diagram, this is the old type (four wires) and your '73 Z should have the newer type (three wires). The '73 diagrams don't seem to have been updated to reflect this.

 

With the four wire setup, the voltage supply is routed through the tacho, with the three wire setup, a wire (green?) from the tacho is connected to the coil (-) terminal.

 

1. Could you remove the tach by loosening the two wing bolts on the back and do a photo of the backside/wires?

 

2. You might want to try this test, remove the b/w wire from coil (+) and HEI module, and temporarily connect a wire to coil (+)/HEI module directly to battery (+). Take care not to create a short circuit. Then try the starter test and check if the test light blinks or if you get a spark. (Do not connect the coil king wire to the distributor with this test)

[Mikez31ss]

The third b/w wire would be the voltage feed for the throttle opener relay, correct. I am not sure about the tach in the wiring diagram, this is the old type (four wires) and your '73 Z should have the newer type (three wires). The '73 diagrams don't seem to have been updated to reflect this.

 

With the four wire setup, the voltage supply is routed through the tacho, with the three wire setup, a wire (green?) from the tacho is connected to the coil (-) terminal.

 

1. Could you remove the tach by loosening the two wing bolts on the back and do a photo of the backside/wires?

 

2. You might want to try this test, remove the b/w wire from coil (+) and HEI module, and temporarily connect a wire to coil (+)/HEI module directly to battery (+). Take care not to create a short circuit. Then try the starter test and check if the test light blinks or if you get a spark. (Do not connect the coil king wire to the distributor with this test)

I haven't had a chance to get back to this recently but I'll try your suggestions out tomorrow.

It's going to be hard to get my big hands up under the dash to reach the tach bolts.

That direct wire to battery test...is that to determine if the problem is between the coil and distributor?

I admit I'm completely stumped at this point. There is power to the coil, the chances of 3 new pick-up coils, 2 new IC modules, and 2 coils all being defective seem pretty slim. And the wiring is too simple to be wrong.

[Mikez31ss]

Pics of the tach:

And the connector:

And some misc pics of the wiring that I need to take a closer look at and ID the wires:

My link

[vantage]

I haven't had a chance to get back to this recently but I'll try your suggestions out tomorrow.

It's going to be hard to get my big hands up under the dash to reach the tach bolts.

That direct wire to battery test...is that to determine if the problem is between the coil and distributor?

I admit I'm completely stumped at this point. There is power to the coil, the chances of 3 new pick-up coils, 2 new IC modules, and 2 coils all being defective seem pretty slim. And the wiring is too simple to be wrong.

 

Thanks for the photos! So you have a four wire tach, which needs to be wired inline with coil (+) and the ballast resistor or black/white coming from the ignition key, if you drop the ballast resistor. (See the wiring diagram in my post #26). Lets fix the tach wiring after you got the HEI up and running.

 

The direct wire to the battery test is to rule out any issues there might be with the b/w and g/w wire supplying the +12V to the ignition and just focus on getting the HEI working with the pickup. If this setup does not work, try to reverse the pickup wires, e.g. red to Hei 'G' and green to HEI 'R'.

[Mikez31ss]

Thanks for the photos! So you have a four wire tach, which needs to be wired inline with coil (+) and the ballast resistor or black/white coming from the ignition key, if you drop the ballast resistor. (See the wiring diagram in my post #26). Lets fix the tach wiring after you got the HEI up and running.

 

The direct wire to the battery test is to rule out any issues there might be with the b/w and g/w wire supplying the +12V to the ignition and just focus on getting the HEI working with the pickup. If this setup does not work, try to reverse the pickup wires, e.g. red to Hei 'G' and green to HEI 'R'.

I'm going to have to review your posts to see if I can understand wiring up the coil and a test light to the battery.

[vantage]

The image i have attached to my last post should explain everything. Wire battery (+) to HEI 'B' and the testlight, and the other side of the testlight to HEI 'C'. When you turn the starter, the bulb should flicker. Normally the bulb goes on as soon as you put +12V on B and the testlight, but that depends on the HEI module.

[Mikez31ss]

So the coil and the black/white wire are left out of the circuit?

Edit:

I guess so...I ran a wire from the coil "+" to the battery. When I touched the ground cable to the battery "-" there was clicking and light from inside the car

I don't know what that was but

I didn't have time to keep at it. I'll try it w/o the coil and black/white wire tomorrow.

Edited April 6, 2010 by Mikez31ss

[vantage]

So the coil and the black/white wire are left out of the circuit?

Edit:

I guess so...I ran a wire from the coil "+" to the battery. When I touched the ground cable to the battery "-" there was clicking and light from inside the car

I don't know what that was but

I didn't have time to keep at it. I'll try it w/o the coil and black/white wire tomorrow.

 

You don't need the coil for this test, just remove the two existing wires from the HEI terminal B and C, then connect battery (+) and the testlight exactly as shown in the chart

[Mikez31ss]

You don't need the coil for this test, just remove the two existing wires from the HEI terminal B and C, then connect battery (+) and the testlight exactly as shown in the chart

Ok it's done but with disappointing results. There was no light and therefor no light pulsations. I tried reversing the pickup coil wires as well. I could get a light between B and ground but not B and C. I tried the e1280 module as well. Same results. I checked the pickup coil again and got 900-1000 ohms.

The air gap is set properly. When I installed the pickup coil I put the thin metal plate between the pickup coil and the reluctor but I think that's the way it was originally. The cap and rotor are new. I can't think of anything else.

[vantage]

Ok it's done but with disappointing results. There was no light and therefor no light pulsations. I tried reversing the pickup coil wires as well. I could get a light between B and ground but not B and C. I tried the e1280 module as well. Same results. I checked the pickup coil again and got 900-1000 ohms.

The air gap is set properly. When I installed the pickup coil I put the thin metal plate between the pickup coil and the reluctor but I think that's the way it was originally. The cap and rotor are new. I can't think of anything else.

 

So you have tried two HEI modules and one E12-80 module without success, i think we need to take a closer look at the distributor too. I have attached an exploded view of the 280ZX distributor so you can check if the thin metal plate you mentioned is correctly placed.

 

 

Two tests to check if the distributor or the HEI module is defective:

 

1. If you set your Multimeter to measure AC voltage (lowest range like 10 Volt or less) and connect the black wire to green of the distributor, and red wire to red of the distributor, you should see a small voltage (around 0.5-2 Volt) as long as you turn the starter. If there is no reading at all (still 0 Volt), then there is something wrong with the distributor and pickup.

 

 

Please repeat the bulb test from my last post, but this time do not connect the distributor to HEI 'R' and HEI 'G', but:

 

2a. instead use a short wire to connect HEI 'R' to HEI 'G' several times, does the bulb blink each time?

 

2b. If 2a. did not work, touch the HEI module 'G' terminal several times with a short wire which is connected to battery (+), does the bulb blink now?

 

 

Best,

Adrian

[Mikez31ss]

So you have tried two HEI modules and one E12-80 module without success, i think we need to take a closer look at the distributor too. I have attached an exploded view of the 280ZX distributor so you can check if the thin metal plate you mentioned is correctly placed.

 

 

Two tests to check if the distributor or the HEI module is defective:

 

1. If you set your Multimeter to measure AC voltage (lowest range like 10 Volt or less) and connect the black wire to green of the distributor, and red wire to red of the distributor, you should see a small voltage (around 0.5-2 Volt) as long as you turn the starter. If there is no reading at all (still 0 Volt), then there is something wrong with the distributor and pickup.

 

 

Please repeat the bulb test from my last post, but this time do not connect the distributor to HEI 'R' and HEI 'G', but:

 

2a. instead use a short wire to connect HEI 'R' to HEI 'G' several times, does the bulb blink each time?

 

2b. If 2a. did not work, touch the HEI module 'G' terminal several times with a short wire which is connected to battery (+), does the bulb blink now?

 

 

Best,

Adrian

Thanks for the diagram. I don't see the metal plate there.

 

Test#1. I don't know if I'll be able to do that one working alone. This test is with everything connected right?

 

2a results...no light at all. Same for 2b.

Without getting too detailed...my financial situation is bad and I'm on the verge of being homeless. I think it may be time to reinstall the points distributor to get the car running and put it back up for sale. Thanks Adrian.

[vantage]

Thanks for the diagram. I don't see the metal plate there.

 

Test#1. I don't know if I'll be able to do that one working alone. This test is with everything connected right?

 

2a results...no light at all. Same for 2b.

Without getting too detailed...my financial situation is bad and I'm on the verge of being homeless. I think it may be time to reinstall the points distributor to get the car running and put it back up for sale. Thanks Adrian.

 

Mike,

 

the test 1 is just with the distributor pickup connected to the multimeter. 2a/2b would indicate that the HEI module is broken, maybe the dealer accidentally send the same module back? It is highly unlikely that both tests would not work with a functional module.

I am very sorry to hear about your situation, wish you good luck and may things get better for you soon!

 

Best,

Adrian

[Mikez31ss]

Mike,

 

the test 1 is just with the distributor pickup connected to the multimeter. 2a/2b would indicate that the HEI module is broken, maybe the dealer accidentally send the same module back? It is highly unlikely that both tests would not work with a functional module.

I am very sorry to hear about your situation, wish you good luck and may things get better for you soon!

 

Best,

Adrian

I managed to do test 1. There was no voltage. I bought the new module before sending the old one back so it's definitely not the same part. What are the odds of getting so many defective parts? Pretty high I'd guess

I must be missing something obvious here but I can't see it. The circuit is so simple. Sorry about mentioning the personal situation. It just slipped out. Situation hopeless but not serious

[vantage]

I managed to do test 1. There was no voltage. I bought the new module before sending the old one back so it's definitely not the same part. What are the odds of getting so many defective parts? Pretty high I'd guess

I must be missing something obvious here but I can't see it. The circuit is so simple. Sorry about mentioning the personal situation. It just slipped out. Situation hopeless but not serious

 

Aha! Test 1 would explain why both the HEI module and the E12-80 did not work. You have checked the resistance of the coil, so the coil itself is ok but there seems to be something wrong with the magnetic components, which create the output voltage.

 

The metal plate you mentioned before might be the problem, could you remove the plate and do test 1 again?

[Mikez31ss]

Aha! Test 1 would explain why both the HEI module and the E12-80 did not work. You have checked the resistance of the coil, so the coil itself is ok but there seems to be something wrong with the magnetic components, which create the output voltage.

 

The metal plate you mentioned before might be the problem, could you remove the plate and do test 1 again?

I removed the plate but it didn't have any effect. There doesn't really seem to be anything else in the dizzy that is replaceable. Timing advance mechanism, but that wouldn't prevent spark would it? The magnet looks good.

[vantage]

I removed the plate but it didn't have any effect. There doesn't really seem to be anything else in the dizzy that is replaceable. Timing advance mechanism, but that wouldn't prevent spark would it? The magnet looks good.

 

There is a very good chance that the distributor is the main problem in your ignition setup based on the results of the latest tests you did. Lets ignore the HEI module for now until we can be sure that the distributor pickup is doing its job.

 

The main problem with the magnetic trigger in the distributor is that you would need specialized equipment to do a thorough test, e.g. a scope would be ideal to see whats going on. Do you have an electronics shop/radio repair shop in your area, which could help? The distributor test with a scope is quite simple, connect the two wires of the pickup coil to the scope's test wires, and turn the distributor axle by hand. If scope's screen shows a "square wave" or "triangle shape", then the distributor is ok. If you just get a flat line, then its broken.

 

If you don't have access to a scope, then here is a cheap homemade workaround test. Buy a cheap red LED at an electronics or parts store, should cost only some cents. Wire the long terminal to the red wire and the short terminal to the green wire.

Now turn the distributor axle by hand, start slowly and gradually get faster. The LED should start to flicker at some speed (do this in a dark room, not in the bright sunlight). If the LED does not flicker even if you turn the axle quite fast, then the distributor coil does not get a magnetic field, e.g. the coil/magnet needs to get replaced or reassembled properly.

 

I would happily test all your ignition components, but sending them across the globe is unfortunately not very ecomonic. Maybe a forum member with the right test equipment lives next to you and can lend a hand?

 

You mentioned that the distributor has been refurbished, do you still have a warranty in place? Then the problem of testing and fixing the distributor could be delegated back at the seller.

[Mikez31ss]

Thanks Adrian. The distributor was purchased in December. It had a 30 or 90 day warranty so it's too late to send it back.

I'll see if I can find an electronics repair shop around or a friend with an oscilloscope.

I disassembled part of the dizzy to look for anything obvious. I don't see anything but here are some pics if you want to take a look. That plate look more like an aesthetic part than a functioning part but who knows. It was on the original pickup coil. There was no plate included with either replacement coil.

I've seen some vids on youtube with a drill attached to the dizzy shaft to turn it. Does it need to turn that fast?

 

 

 

 

 

 

 

 

 

 

 

[vantage]

I don't see anything unusual regarding the distributor (great photos btw, thanks), looks good to me. The plate is a plastic insulation for the coil, makes sense to have that in place. You don't need a drill, just give the distributor axle a quick spin with your fingers, that should be enough to get a result.

BTW, will get a Proform 66944C for testing end of this week, then i'll know more how it should behave

[vantage]

Got hold of a Proform 66944C for testing, the second bulb test i have described works with the module to check its health. Wire it as in the included chart, when you then touch terminal 'G' with a wire coming from 'B', the bulb should flash. Can you do this test and let us know how it turned out?