Setting Timing

[Large Arbor]

Is that telling me the magnetic pickup is bad?

Phil

[patrickt]

Originally Posted by Large Arbor

Is that telling me the magnetic pickup is bad?

Phil

No, the pickup is a different test and does a different chore. So you can't get a connection between the coil terminal and any of the eight perimeter terminals even when you turn the gear with your fingers? Then there is something wrong under the cap. If you remove the cap, you can see that all the rotor does is connect the middle coil terminal to one of the eight terminals around the perimeter. Either you are doing this test wrong, or there is something wrong with the cap and rotor connections.

[patrickt]

Even if there was just the tiniest gap between the rotor tip and the terminals, that would be jumped easily by high voltage, but not register as connected with a VOM, I would think the rotor tip would touch at least some of the terminals as you rotate the gear. Any chance the rotor prong is not touching the iron ball?

[Gaz64]

Originally Posted by patrickt

Even if there was just the tiniest gap between the rotor tip and the terminals, that would be jumped easily by high voltage, but not register as connected with a VOM, I would think the rotor tip would touch at least some of the terminals as you rotate the gear. Any chance the rotor prong is not touching the iron ball?

This will not work as a test, I have never heard of anybody doing this.

EVERY distributor has a tiny airgap between the rotor tip and the spark plug terminal.

[Gaz64]

Sit the cap on the rotor button, you should feel the spring loaded contact of the carbon brush.

If the cap just sits there on it's own, there is no contact at the rotor centre contact with the carbon brush.

Sounds like a mismatched cap and rotor button.

[Bernica]

Originally Posted by Gaz64

This will not work as a test, I have never heard of anybody doing this.

EVERY distributor has a tiny airgap between the rotor tip and the spark plug terminal.

That was my thought too, but I figured it was just how PatrickT wrote the post.
You are correct. There has to be small gap for the spark to arc from the rotor tip to the individual spark plug lead. But PatrickT knows this!!

[Bernica]

Many folks carry an extra new MSD cap in their trunk just because of this kind of problem.

[Bernica]

Originally Posted by Bernica

Many folks carry an extra new MSD cap in their trunk just because of this kind of problem.

And also one reason I got rid of my entire MSD system and put the Pertronix dizzy in!!

[patrickt]

Originally Posted by Gaz64

This will not work as a test, I have never heard of anybody doing this.

EVERY distributor has a tiny airgap between the rotor tip and the spark plug terminal.

I don't know. I think they do actually touch, but they very well might not. But, it's certainly not definitive. I don't know why he would only get spark to two cylinders without something being wrong under the cap.

[Gaz64]

In a perfect world they would touch, but it would be noisy until the contacts wore each other out to zero clearance.

Some rotor buttons have adjustable tips for those who like to set minimum gap.

If you can get .001 across all terminals, you are doing well.

I think the OP is chasing a component fault.
Either weak coil, bad pickup, or bad module, or possibly bad wiring installation.

Myself, I would chuck all the MSD stuff out, start fresh with Mallory or Pertronix.

[Bernica]

Originally Posted by patrickt

I don't know. I think they do actually touch, but they very well might not. But, it's certainly not definitive. I don't know why he would only get spark to two cylinders without something being wrong under the cap.

No way they could be touching. Two hard parts (rotor tip and plug contact) rubbing together? They would either clearance themselves or break something.

[Gaz64]

Originally Posted by Bernica

No way they could be touching. Two hard parts (rotor tip and plug contact) rubbing together? They would either clearance themselves or break something.

That's correct.