1971 240Z Not Getting Spark

[austinnelson117]

Hello all, I have gotten my Z to the point where it is time to turn it over and see what happens. So far nothing. It is not getting any spark at the plugs or at the wire coming out of the ignition coil that leads to the distributor. I tried to follow the wiring from the Haynes manual but it shows only 1 positive wire at the ignition coil and I have 3. 2 of them beep on the multimeter ONLY when the ignition is turned and the third one beeps at all times. Then I have one negative coming through the wire bundle as well that connects just above the distributor. I am getting power into the ignition coil just not out of it. What am I doing wrong here??

[Alex K]

Or does anyone have a wiring diagram besides any that google show, or that are in the book? Maybe some pictures of your stock engine? All of the wires are live, it's just a matter of hooking them up correctly. We have yet to find a decent wiring diagram. We tried our brains and messed around with different combinations, but nothing seems to get it to spark.

[philbar73]

There ia a wiring diagram on this site that may help. http://www.classiczcars.com/forums/downloads.php?do=file&id=3 Its under downloads on the right side of the home page. Hope it helps.

[FastWoman]

Additionally, Hanes manuals are useless. You can download Nissan's Factory Service Manual at www.xenons30.com.

That said, a points ignition system is pretty simple. With the ignition on, you should have +12 constantly to the + post of the coil. The points in the distributor are like a telegraph key and will alternately ground and lift the ground to the (-) post of the coil. When this happens, a spark will be generated. If you connect the black probe of your multimeter to ground and your red probe to the coil's (-) post, you should see the voltage fluctuate between +12 and 0 as the engine slowly cranks. (Well, there might be a drop resistor inserted in there, so maybe these are not the correct figures, but it will fluctuate.

If the voltage is fluctuating, but you have no spark, then your coil is bad. If the voltage isn't fluctuating, then something might be wrong with your points.

Edited October 13, 2011 by FastWoman

[Alex K]

Thank you for that. The schematic helps.

Maybe someone will read this and understand....

-At the location of the ignition we have a green wire with a white stripe that is ONLY active when we turn the key.

-2 Positive black wires with white stripes.

-Yellow wire that grounds to engine

-Black wire that looks like it would connected to the distributor as a ground, but while testing for complete circuits, we couldn't find a reason to call that location a ground.

We also had what looked like a small capacitor/condenser that was sitting around. Maybe we need to use that?

[Zed Head]

Don't forget to adjust the points. They have to close and open to make and break the primary circuit in the coil. The condenser will stop your points from pitting and give you a stronger spark but is not necessary.

[SteveJ]

There is an important detail missing. Is this a stock ignition system? If so, have you checked the gap & dwell on your points?

For a stock system

In the start position, the green/white wire is energized from the white/red wire at the ignition switch. It goes through the tachometer and on to the black/white wire that goes to the positive side of the coil. In the run position, there is a black/white wire that is energized from the white/red wire at the ignition switch. It goes through the ballast resistor (dropping down to about 9 VDC) and on to the green/white wire.

The black wire does go from the coil to the distributor. The ground you are looking for actually goes through the condensor (capacitor). It would go off of the negative side of the coil.

[LeonV]

First thing that came to my mind is your points aren't opening. As others have suggested, check point gap.

[austinnelson117]

Ok well I'm not 100% sure what is and isn't stock, the previous owner did mention something about switching over to electronic ignition but I'm not sure exactly what was done. I will probably call him this evening to confirm. But, according to your description of the wires everything sounds about right. One problem we had was the ground on the distributor that connects to the coil was not reading when the other end of the multimeter was connected to the positive battery terminal. We just made our own ground for the time being just to test it but im not sure if that has anything to do with the problem. Also, where does the green/white wire connect to the ignition set up? We followed the manual to a T but came up blank. And Steve, we are learning as we go here but I have no earthly clue how to check the gap and dwell of the ponts. Do you mean the gap on the spark plugs? I will do some reasearch to try and learn a little more about it but like I said we followed every wiring diagram we found exactly.

[LeonV]

Did you download the FSM yet? It's all in there. Get the '72 FSM from Xenon's site that you've been linked to and is in Steve's signature. Everything should be similar, if not identical, to a stock '71, especially reguarding the ignition system.

[Alex K]

Yes we are using this diagram.

http://www.classiczcars.com/forums/attachment.php?attachmentid=10508&d=1135999612

[LeonV]

The FSM is not just good for the wiring diagrams, but also for everything else concerning the Z. Don't know what's stock? Check the FSM. Don't know what point gap is? Check the FSM. Googling terms you don't know (like point gap) will help.