'70 240Z MSD No Spark 280z Distributor, E12-80, 280Z Tach

[YoshiDori]

Hello,

I have been searching and reading for the past month trying to make sure I understand. It's more so information overload. Was hoping someone here who understands better than I could lend some insight.

Anyhow, background:

Car: 1970 Datsun 240Z
Distributor: 280ZX with E12-80 Module
Tach: 280Z internals swapped into 240Z Housing
Coil: MSD Blaster 2

Okay, so I have bypassed the ballast resister and connected those two wires(BW to GW). Then took the keyed 12v source that became live after connecting the two ballast wires (BW) and ran that to the "+" terminal on the coil. From the "+" I ran a new wire to the B connector on the E12-80. From the C connector I ran a wire to the "-" terminal on the coil. Then I have a wire coming from the "-" terminal that will run to the tach. (Not connected yet). Also ran a new ground wire from the tab on the vacuum advance to ground.

When I turn the key, the engine turns over, but I get no spark at the plugs. So I checked from the coil by trying to arc it off a ground and nothing happens.

I tested the MSD coil and I have .7 ohms from "+" to "-" terminal as I should and 5,500 ohms from "+" to coil wire which is what it's supposed to be. I have 12v at the + and 12v at the -... I don't think that is right.

I have tried to read everything I can and interpret different issues that people have had into my own and as you can tell I'm having trouble. Wiring is not my strong suit so any help would be greatly appreciated.

I hope I'm not beating a dead horse here and overlooked a thread that would answer all my questions. Again all help is appreciated!

Thanks,
-Josh

Edited May 30, 2016 by YoshiDori

[Zed Head]

Your wiring seems right.  "  12v at the + and 12v at the - " is correct, the voltage is the same because the ignition module is not grounding the coil circuit.

You didn't give any information about the distributor.  You might have a bad module or a broken stator magnet.  Pretty common with the old ZX distributors.

Read the swap and rebuild ZX distributor links here - http://atlanticz.ca/zclub/techtips/electrical.htm

[YoshiDori]

Awesome thanks! I'll do some reading.

The distributor came off a 280zx and had a different module. I bought an e12-80 off line as a new aftermarket module and swapped it onto the distributor. Also have the 280z base as well.

[YoshiDori]

I've previously read the distributor swap post you suggested. There are some differences in wiring colors etc, but it seems okay. The repair one, looks like my stator is okay. I'm going take a closer look tomorrow. The cap and rotor are new.

Is there a way to get the coil to spark besides through the distributor?

[sweatybetty]

unhook the wire on the - side of the coil, then use a jumper wire from the - side of the coil to a good ground. it should spark when you touch it to ground and then pull it away

Edited May 30, 2016 by sweatybetty

[YoshiDori]

Yes, it does spark when I ground the "-"

 

*edit* just to be clear, it sparks between the ground an "-" terminal. Will check to see if coil actually fires in the morning. *edit*

Edited May 30, 2016 by YoshiDori

[Zed Head]

The part that many people seem to have the most difficulty with on these cars is the need to do lots of measuring and adjusting or fixing if the measurements are wrong.  At least you have a meter and are using it.  You just need to go deeper.

You didn't mention pickup coil resistance or the air gap setting.  The electronic module won't work right if it doesn't get the correct signal from the pickup coil.  Your coil and wires seem fine, it's the triggering system that's not working.

 

 

 

[YoshiDori]

Okay. Couldn't sleep. If I put the coil wire very close to a ground and then jump the "-" terminal to ground and remove it, it does spark, but it's very weak and has to be pretty close... not sure if that is good or bad.

[Zed Head]

Remove the distributor from the engine and do the same thing with the coil main wire, but spin the distributor instead, with the key on.  If the distributor and module are working you should get the same weak spark.

[Zed Head]

Or disconnect the E12-80 module and do the same test you just did over again.  If the module is shorted internally you'll get a stronger spark.

[YoshiDori]

Awesome! Thanks for the input! I will check resistance of pickup coil and measure air gaps. I will also repeat the test as you suggested. Should the spark be weak?

And what resistance should the pickup coil have?

Edited May 30, 2016 by YoshiDori

[siteunseen]

The ZX distributor needs 1.3 OHMs primary resistance according to the FSM.  Those Blaster 2s only have .7 OHM.  I don't know what affect that will have but that's the reason I chose a Fireball PS20.  They are 1.5 OHMs.

Zed Head can explain it.