Timing Off Runs Bad

[Zed Head]

Don't forget that the spark happens when the magnet on the shaft passes by the Pertronix sensor.  One more thing to line up.  Trigger, rotor, compression stroke on #1, plug wire.

The magnets have been known to fall off.  

[ZNate]

SteveJ: Thank you for your research.

There should be two adjustment bolts for timing. Have you played with both?
(No, just the 10mm Phillips head to advance or retard timing.)

If you have, and what you said still holds, here is what you might do.

1. Put the mark at the first line past the middle and toward retard. Consider that your static zero position. (Okay, will adjust the rotor a little to “zero” it.)

2. Adjust the oil pump from there to put the rotor at TDC.  (Not sure what you you are saying.  The rotor at 11:25 in the photo matches the oil pump shaft at TDC.  I think the Mallory dual point distributor, with no vacuum, is an odd duck.

Originally, the #1 plug wire was at 12:00 and the rotor/oil pump shaft at TDC pointed to 1:35.  Engine ran bad then too.

Zed Head: Thank you for your clarification.  Of the things to line up (trigger, rotor, compression stroke on #1 and #1 plug wire) I can only line up the rotor (11:25) and compression stroke on #1.  The distributor positions for #1 plug wire is about 10:00 or 12:00.  Have no knowledge on how triggering happens.

So should I reposition the #1 plug wire to 12:00 and adjust the oil pump shaft so it aligns just right of 12:00?  Otherwise, I have no idea where to go other than to throw money at it (different distributor, electronic ignition, etc).

The photos show where everything is positioned right now.

 

[Zed Head]

13 minutes ago, ZNate said:

Have no knowledge on how triggering happens.

You're working on a modified system so knowledge of how the ignition system works would help you a lot.  Even if you installed the distributor and oil pump shaft exactly as Nissan instructs, the odd parts in the distributor will probably be off.  You have Nissan, Mallory and Pertronix all combined.

The Pertronix is a Hall effect sensor so you can use a meter to determine when the magnet passes the sensor.  But...more knowledge required.

If you remove the rotor and take a picture of the top of the magnet ring the position of the magnet might be apparent.  It's important.

And, just in case you bumped something, the gap between magnet and sensor needs to be right.  It can cause sporadic spark if it's not.

 

[SteveJ]

As for the bolts to adjust the timing, there's a picture for that.

Here's a YouTube video where a guy made a transitorized ignition with a Hall effect sensor. You'll see early in the video that he passes a magnet over the sensor, and you can see the spark.

For the Pertronix ignitor, there are magnets in the ring that goes below the rotor. The ring should be indexed to fit over the shaft only one way.

Otherwise, I don't have much to add to what @Zed Head said.

[Zed Head]

You could get everything aligned and set up the coil's center wire close to a ground where you can see the spark.  Then turn the key on and twist the distributor until a spark happens.  You'll be moving the sensor past a magnet instead of vice versa.  Move it around until the spark happens where you like it and put your #1 plug wire at the proper spot on the cap.  You should be close then.

[ZNate]

Revised: Originally, the #1 plug wire was at 12:00 and the rotor/oil pump shaft at TDC pointed to somewhere around 12:35 to 1:35.  Engine ran bad then too.

Zed Head: Took some photos as you suggested.  I found the mark on the magnet ring.  When installed the mark lines up with the oil pump shaft and rotor.  So the #1 plug wire is only thing that does not line up.

It appears that my Pertronix version 1 does not have any gap adjustment.  Have about 1500 miles on the system over past 2-3 summers.

[ZNate]

Zed Head & SteveJ: Thanks again for the suggestions.

Will try the distributor twist with the key on and get back with you.

[Zed Head]

Here's an old thread showing the green tape and the magnets underneath.  There are six magnets.

Might just help you absorb all that's been written so far.  We're still at trying to get spark to happen on the #1 plug wire when #1 piston is at about 10 degrees before TDC on its compression stroke.  You've pretty much covered all of the separate issues, just need to to put them together.

 

[ZNate]

The full twist left or right does not line up with #1, so no spark.  Even if I move #1 to a different post on the distributor, there will not be an alignment/spark.

I think I need to move the oil pump shaft so I can set up an alignment of the rotor and a distributor post.  Should the rotor/shaft align exactly to a post or slightly before/after?  

Originally the rotor aligned slightly before the #1 plug wire/post, but the timing was around 20 degrees advanced, with no adjustment left to retard the timing.

[Zed Head]

Did you try the coil main wire to check for spark?  Maybe your ignition system is weak or dying and that's why you 've been having problems.

You shouldn't be able to get a full twist on the distributor without one magnet at least passing by the sensor.  You should be able to generate a spark.

The twist is not meant to line up the rotor, it's meant to move the sensor past a magnet, to generate a spark.  Make a spark then see if you can get the rotor pointed at a terminal.

[ZNate]

I guess I need to determine 10 degrees BTDC for aligning the oil pump shaft?  Is there a way to measure or identify this spot this or is it trial and error?  If the distributor post is at 12:00, then the rotor needs to be at 12:35?

[ZNate]

Zed Head: I pulled the coil wire from the coil for testing.  I'll try again with a different ground.