Starting issue

[Gaz64]

David,

If you have a 6AL, there is not 12v at the ignition coil, there is some 480v with the engine running, since you have a CD ignition, not inductive ignition.

The coil primary terminals are more dangerous in a CD ignition.

After reading your opening statement, I wasn't surprised to see you have a MSD ignition fault.

Now, onto some testing.

Can you disconnect your mag trigger harness at the distributor, remove the coil wire from the distributor, set up the coil wire with 1/2 inch gap to ground.

Get yourself a paperclip, form a horseshoe.

Then ignition key on, bridge the mag harness that goes towards the 6AL module in rapid on/offs. Does spark jump across your 1/2 gap?

Gary

[Kit Coyle]

Buy a Lucas bezel removal tool. I bought one from Moss Motors, Ltd.
TOOL SET, SWITCH BEZEL REMOVAL...part#384-960...$29.99...on sale for
$21.99.

[patrickt]

Dave, you do not need to remove your ignition switch, the terminals are easily reachable from under the dash. But, if you feel the need to remove it, it's pretty easy to just make a "two prong" tool that fits the two slots around the switch. It just unscrews and your ignition switch is very easy to change out. I did mine about ten years ago and it was a ten minute job. That said, a "no spark" condition with the MSD box is the easiest to diagnose no start condition there is. Don't take any VOM measurements, don't jump to any conclusions, just follow these instructions: https://www.holley.com/support/troub...ng_techniques/ The hardest part is just figuring out whether you're using a white wire trigger or the purple/green trigger. It's either going to be: 1) a bad magnetic pickup; 2) a bad coil; 3) a bad MSD box; 4) a bad distributor cap/rotor; 5) a bad 12v feed to the box.

[Gaz64]

Thanks for adding the trouble-shooting link Patrick.

Good to see it states the differences as to why no 12v at the coil.

[patrickt]

Originally Posted by Gaz64

Thanks for adding the trouble-shooting link Patrick.

Good to see it states the differences as to why no 12v at the coil.

Ahhh, the good ol' days when you could charge up a 400v capacitor and then playfully toss it to a friend and yell "catch!"

[Gaz64]

Originally Posted by patrickt

Ahhh, the good ol' days when you could charge up a 400v capacitor and then playfully toss it to a friend and yell "catch!"

Yes, seen that at college, , about 38 years ago for me.

[davids2toys]

Originally Posted by patrickt

Dave, you do not need to remove your ignition switch, the terminals are easily reachable from under the dash. But, if you feel the need to remove it, it's pretty easy to just make a "two prong" tool that fits the two slots around the switch. It just unscrews and your ignition switch is very easy to change out. I did mine about ten years ago and it was a ten minute job. That said, a "no spark" condition with the MSD box is the easiest to diagnose no start condition there is. Don't take any VOM measurements, don't jump to any conclusions, just follow these instructions: https://www.holley.com/support/troub...ng_techniques/ The hardest part is just figuring out whether you're using a white wire trigger or the purple/green trigger. It's either going to be: 1) a bad magnetic pickup; 2) a bad coil; 3) a bad MSD box; 4) a bad distributor cap/rotor; 5) a bad 12v feed to the box.

Pat, I am only 12 weeks post op from back surgery/fusion. I would rather be safe than sorry. I am still pretty stiff and sore. Even if I removed the seat it would be a challenge. I figured it would be much easier just popping it out of the hole and testing it ad tracing wires in the hanging down position. As I said, this bezel was not moving more than an 1/8". I remember changing the switch in my first Cobra, as you said, piece of cake!
Great link, I also found it late last night. I will be doing all of these things. I might get a little time Thursday morning, but probably not.I feel better because you are making this sound much easier and less scarier. By the way, I have that purple/green trigger connector.
As I said, I hate electrical.
As usual Pat, your vast knowledge is always so helpful...THANKS.
I will report back on my progress

[patrickt]

Originally Posted by davids2toys

Pat, I am only 12 weeks post op from back surgery/fusion. I would rather be safe than sorry. I am still pretty stiff and sore.

The beauty of the MSD box and the ERA wiring harness is that you can check voltage/continuity without always having to crawl under the dash or under the car to get to the spot that you think needs testing -- which pretty much sucks when your back hurts. For example, you can check your ignition switch, for the most part, over at your starter solenoid (which is really easy to reach), because of the way ERA wires in the little red and orange trigger and tach wires. When the MSD box is over the passenger's feet, you would think that the little red and orange trigger/tach wires would just run two feet directly over to the ignition switch and tach, but it usually doesn't. It goes out through the firewall, around the block, and up to the wiring harness by the distributor. This is because the harness also has to support "legacy" ignitions that feed 12v+ to the coil. The ballast resistor connections along that line are just fused together, but you still have the offshoot of that connection heading off to the starter solenoid. The long and the short of that means three things: 1) You can hotwire and start up an ERA/MSD car with a two inch piece of wire and an aluminum foil gum wrapper; 2) a misbehaving starter solenoid can actually keep your car running even when you remove the key from the ignition; and, more importantly, 3) You can check the continuity and function of your MSD ignition system without having to bend your back much at all. I'll lead you through it when you're ready, but it's really, really, really easy to do.

[patrickt]

Here's a handy little diagram from ERA's site on how the MSD is wired in to the harness. If you look up at the top of the picture you see connection #40, which normally goes to an old style 12v coil. The white wire would normally go to the positive side of the coil and is coming from the ignition switch. It may be reduced by a ballast resistor in an original set up, but it is now connected directly to the little red wire of the MSD box. The orange wire goes to the negative side of the coil and is your tachometer feed. This white wire is the same white wire that you see attached to the "I" side of the starter solenoid (but the picture doesn't show that). This makes it very easy to check whether your ignition switch is working and whether you're providing 12v+ "turn on the box voltage" to the MSD box. Just turn your ignition key "ON" and if the accessories light up then you know the "ACC" portion of your ignition switch is operating. Then measure the voltage at the "I" terminal of your solenoid. If you have 12v+, then you know the "IGN" portion of your switch is operating and the box is being turned on, and if you get 12v+ at the "S" terminal of your solenoid, when turning the key to the cranking position, then you know your "ST" portion of the switch is working fine. Of course, if you hear your engine cranking then you don't even have to take that last measurement. Short of a broken wire, that's all there is to it. The next step is to just follow the trouble shooting steps that MSD lays out. There is no magic to this, no voodoo, no tricks. It's not even that hard. You can do this.

[Gaz64]

Are you ready to do the mag pickup test for spark with a paperclip?

As Patrick has mentioned, very easy to do.

Gary

[davids2toys]

Originally Posted by Kit Coyle

Buy a Lucas bezel removal tool. I bought one from Moss Motors, Ltd.
TOOL SET, SWITCH BEZEL REMOVAL...part#384-960...$29.99...on sale for
$21.99.

One or our local ERA forum members had made one for his Cobra 13 years ago. I am picking it up tomorrow. I will just break the bezel free in case I have to test or replace it, and then return it.
Thank you for the tool info

[davids2toys]

Originally Posted by Kit Coyle

Buy a Lucas bezel removal tool. I bought one from Moss Motors, Ltd.
TOOL SET, SWITCH BEZEL REMOVAL...part#384-960...$29.99...on sale for
$21.99.

Cool tool, I decided to order it, I'm sure I will need it one day.
Thanks

[davids2toys]

Originally Posted by Gaz64

David,

If you have a 6AL, there is not 12v at the ignition coil, there is some 480v with the engine running, since you have a CD ignition, not inductive ignition.

The coil primary terminals are more dangerous in a CD ignition.

After reading your opening statement, I wasn't surprised to see you have a MSD ignition fault.

Now, onto some testing.

Can you disconnect your mag trigger harness at the distributor, remove the coil wire from the distributor, set up the coil wire with 1/2 inch gap to ground.

Get yourself a paperclip, form a horseshoe.

Then ignition key on, bridge the mag harness that goes towards the 6AL module in rapid on/offs. Does spark jump across your 1/2 gap?

Gary

Hi Gary,
Just a little over my head here.What is a CD ignition? What opening statement are you referring to? Why are you not surprised?
As far as your testing goes, it unfortunately has to wait. I am leaving for 1 week vacation Sat morning and running around all this week. No time for the Cobra until I return end of next week. I will gather research info and hit it hard when I return end of next week. I will have to get a diagram I can identify the parts you are referring to.
Thanks

[DanEC]

Originally Posted by davids2toys

Hi Gary,
Just a little over my head here.What is a CD ignition?

Capacitor Discharge. Electrical is not my strong suit so instead here is a link.

https://en.wikipedia.org/wiki/Capaci...harge_ignition

[davids2toys]

Originally Posted by DanEC

Capacitor Discharge. Electrical is not my strong suit so instead here is a link.

https://en.wikipedia.org/wiki/Capaci...harge_ignition

Interesting, thanks