No start, no spark

[JoColtrane]

351c, 2v, mallory dizzy., new coil.

I have a no start no spark condition. Car started two weeks ago. Here's a description from a different forum that seems to describe three actions at start.


"When you turn the key to start...
1)Power runs from the ignition switch thru the NSS to the S terminal of the solenoid causing a high amperage of power to travel from the battery to the starter lug of the relay to the starter to crank the engine....

2) At the same time, while the key is in Start, power (12 Volts) from the I terminal runs to the coil for easier starting.

3) Once the key returns to RUN... 7-9 volts are delivered to the coil operating the ignition system."


In my case it appears that the 1st and 3rd actions are occurring because the starter has been tested and is turning over and there's a slight spark on tester when key returns to run position from start). 2nd action does not appear to be occurring.

Here's a video of spark tester attached between coil and dizzy. In the video I turn the engine over twice. Both times you see three sparks. 1st when key goes from off to run, 2nd when key goes from run to start and third when key goes from start back to run. No spark in start position.

View attachment My Movie.mp4

What should I be checking? Is it possible for solenoid to be sending enough power to starter but not out to coil? Just want to make sure I'm on the right path.

Jo

 

[Hemikiller]

Which Mallory distributor are you running?

 

[Cleveland Crush]

Your Orange (weak) spark is a problem. Something upstream of your spark tester is choking voltage i.e. coil, module/points, relay or wiring.

 

[JoColtrane]

Unilite Comp 9000.

I figured as much but I'm not mechanically/electrically inclined therefore I wasn't sure of everything that was upstream of the tester. Can't be the module because this was the wire coming off of the coil prior to the distributor. I considered the the relay, ignition switch and wiring but wasn't sure if I was on the right track. I understand the wiring path between the ignition switch and relay but wasn't sure if there were other wires I should check.

 

[Cleveland Crush]

This is a simple test of your unilite setup. Just one step in the process of elimination.

 

[JoColtrane]

So after some checking the battery measured at 12v, ignition switch measured at 11.7v, and wire (read w/ green stripe) off of switch that terminates at relay (after a couple of connectors) measures at 7.6v so I'm guessing the problem is between the switch and relay.

Please correct me if I'm wrong but options at this point would be to cut original wire run my own wire (the easy but maybe incorrect way) or find connectors and measure voltage there and make correction where the issue is found which would probably still involve running some length of wire.

I believe the first connector is just outside the firewall and the other is near the front just underneath the water reservoir.

 

[JoColtrane]

Oh just saw this on a different forum.

"When you turn the key to start... Power runs from the ignition switch thru the NSS to the S terminal of the solenoid causing a high amperage of power to travel from the battery to the starter lug of the relay to the starter to crank the engine.... At the same time, while the key is in Start, power (12 Volts) from the I terminal runs to the coil for easier starting.

Once the key returns to RUN... 7-9 volts are delivered to the coil operating the ignition system."

So that being said is it safe to say the relay is the issue?

 

[Steve McMahan]

I think I would test the voltage at the coil + terminal when cranking (should be around 12v), and in the run position (should be 6-8v). If that’s true, the problem is not voltage. It’s more likely in the distributor or you have a bad coil. I would start with the distributor. I’m not familiar with the one you have, but with the key in the run position, you can manually move the distributor to open and close the points to see the spark output of the coil. Also, you can test your coil for resistance. I remember reading a post of the stock coil OHM valve it should read. Just a few thoughts.

 

[JoColtrane]

Ok, so this is what I have.

Ignition Switch – 12.3 volts

Battery – 12.5v

Battery Drop – 12.5v

Battery Cable Drop – .1v

Solenoid +post to S terminal – 3.6 ohms

Solenoid battery post voltage – 12.6v

Solenoid S terminal - 12.1v

Solenoid I terminal – Initial reading is 15v for about a millisecond then it drops to 10 while continuing to crank

Solenoid starter post - same as I terminal

Coil resistance is within spec

Coil positive post – 10v

Steve that's kind of what I was thinking therefore all of these seem within spec except for the three places where I measured 10v (I terminal, starter post and + coil post.) I got the 10v measurement with the existing and a new solenoid so that kind of threw me off so I wasn't sure if that was normal. Is it possible that both solenoids were bad? Going to try number three. Any thoughts on the 10v readings.

 

[JoColtrane]

I also forgot to say I'm not sure of how to remove this rotor to get to the module on the dizzy.

 

[Cleveland Crush]

Rotor: work your way around gently with an angle screwdriver or similar. Put a dab of grease on the retaining rubber o-ring during reinstall.

 

[JoColtrane]

So with the ignition in the run position when I disconnected this I had:

Solenoid positive terminal 12v
Solenoid I terminal 12v
Coil negative terminal 12v
Coil positive terminal 12v

When connected I had

Solenoid positive terminal 12v
Solenoid I terminal 8v
Coil negative terminal 1v
Coil positive terminal 4v

No change when module sensor was interrupted. One post on the ballast got hot.

 

[Steve McMahan]

I’m a little confused, what’s new. I thought it was 10v at the coil, which in the run position sounds a little high, since the power should be reduced by the resister wire or ballast resister. It should be 12v at the crank position, but 10v is plenty for start voltage. I’m hoping someone here has a way to test the ignition control module vs replacing it.

For what it’s worth, scanning the forum, there seems to be quite a few folks who have these issues with these aftermarket ignition systems, and then quite a few with zero issues. Kinda what Hemikiller and others have been saying this past year, new parts does not equal good parts.

I think the module could be the culpri. As a test, you can manually power the coil and then remove power to see if it produces a spark to eliminate it from consideration.

 

[JoColtrane]

Steve.

The 10v result was while in cranking position. Those last results were in the run position. Sorrt, I wasn't clear. Pretty much everything you stated is what I was pondering. Thanks.

 

[Hemikiller]

Keep in mind that the voltage at the coil (+) post will only drop when there is a draw, like when the coil is charging.

Found this testing procedure online, not sure if this is what you were performing.

https://centuryperformance.com/tech-zone/mallory-unilite-and-espark-module-testing/?v=b0c4bc877c29

 

[midlife]

Everyone says 9V at the + side of the coil when running. That's BS, and even the Ford Shop Manual says differently. Consider this: every eighth of a engine rotation, a spark is produced. This happens when the points close and there's now a ground for the coil to see, which causes it to discharge voltage to the spark plug. Most of the time, there is no point closure, so no load on the pink resistor wire. The actual voltage at the + side of the coil is supposed to be 10.5 to 11.5V, and I have verified that on my 1966 289.
The 9 volt value comes around as the lowest sustainable voltage to produce good spark, as measured while the car is running.

 

[Steve McMahan]

Good to know Midlife, glad you’re part of this forum.

But, you have verified you have sufficient voltage to work with, so it’s either the coil or the primary voltage interruptor. Once you have tested the coil, and you get a spark, I think the interruptor is the likely culprit.

 

[JoColtrane]

Yes, I tested the coil for resistance and spark. Both were normal. Coil is good.




In this pic the ignition wire goes from ignition to ballast. Correct me if I'm wrong but this is the red wire with blue stripe and it goes to the relay and then the ballast (like in the second pick). If yes should I bypass relay to do this test. Also when I measured today I had 12v at battery, 12v at ignition switch but no measurement on wire that connects to S terminal (red wire with blue stripe). DMM kept fluctuating which usually indicates poor connection. Fitting had some slight corrosion but not so much that it shouldn't give a reading (in my opinion). Maybe this is the issue.

 

[Kilgon]

Going to throw something out there for you to try. Hot wire it and see if it will run. If it does it then it will help to isolate where the problems might be. If you don't know how hot wire our cars it quite simple. Remove the wire from the + terminal on the coil and then run a wire from the battery to the + side on the coil. This will make the ignition hot. Then jump the battery side of the solenoid to the S post to start it. If it starts then you can eliminate the solenoid, distributor and coil. That leave wiring issues, or the ignition switch itself.

 

[midlife]

Yes, I tested the coil for resistance and spark. Both were normal. Coil is good.


View attachment 78166 View attachment 78167

In this pic the ignition wire goes from ignition to ballast. Correct me if I'm wrong but this is the red wire with blue stripe and it goes to the relay and then the ballast (like in the second pick). If yes should I bypass relay to do this test. Also when I measured today I had 12v at battery, 12v at ignition switch but no measurement on wire that connects to S terminal (red wire with blue stripe). DMM kept fluctuating which usually indicates poor connection. Fitting had some slight corrosion but not so much that it shouldn't give a reading (in my opinion). Maybe this is the issue.

Red/blue is crank/neutral safety switch wire. It DOES not go to any relay other than the starter solenoid (post closest to the battery). The coil wire is typically red/green or brown, and you should have a lead on the second post (towards starter motor) that provides a full 12V when cranking.

If that picture is from your car, you need to replace a cable at the battery side (burned insulation and cooked wires) and your starter cable is not nutted down. Your S cable looks awful and may not work; the other wire with no lead is probably the I wire.