No Start with random spark MSD issues
 

Equipment
-427FE with Quickfuel Carb, electric choke
-MSD Distributor with Magnetic Pickup part number 8094
-MSD Digital 6 Plus Ignition Box
-MSD Blaster Coil
-MSD 8mm Spark Plug wires. These are temporary and will be replaced with 8.5mm wires

I had the car running two days ago and the sound from the exhaust indicated that the timing was fairly close to being correct. I restarted the car once after that and let it run for a few seconds and then shut it down. Since then, i have not been able to get the car to start again. Now, before anybody says something about me starting the car for a few seconds and shutting it down...i am using a roller cam, so dont freak out about me ruining a flat tappet cam. :D
I put a timing light on the car yesterday because i was getting an occasional backfire. However, the timing light did not flash at all while cranking the car. So, i put a spark plug on the end of one of the wires and it did spark once, but then nothing. It appears that the ignition will give off a spark occasionally, but not consistently.
So, here is what i have done.

Please allow me to quote the MSD instructions before i begin.
"The reason 12V won’t be present at coil + is because your MSD ignition is a Capacitive Discharge Ignition. Like all CD ignitions they use a large capacitor to discharge 420-480 Volts to coil + and coil – will normally be connected to ground".

1. SPARK

This is per MSDs troubleshooting instructions.
To test for spark:
With a small jumper wire, short the Green and Violet magnetic pickup wires together then pull the jumper off. Each time the short is removed a spark should jump If spark is present, the ignition is working properly.

Yes, I have spark to the distributor at least.

2. WIRING of the MSD Box

-Ground to the battery and to the chassis
-Heavy Red feed wire is connected to the solenoid
-Red wire responsible for turning box on and off is connected to a fused switch that gets power to the box while in the on position and cranking
-Orange goes to + side of coil
-Black goes to - side of coil
-Green and violet run alone, away from other wires, to the distributor
-White is not used
-Green loop has been snipped and sealed
-I'm not using the rev limiter
-Tach is currently not connected

So, the wiring is correct and good to go. The battery read 12.8 volts. BUT, when i crank the engine the voltage at the red wire responsible for turning the box on and off drops to 9 volts. I checked the voltage at the ignition switch and it drops to 9 volts there as well.

3. Magnetic Pickup

I tested the OHM reading on the pickup and it reads 500 ohms, which is within range. HOWEVER, when i spin the distributor at a steady pace in a counterclockwise direction, the OHMS are all over the place reading 0 at some points, a 1000, and 50 at others. Its a constant change. Perhaps it is supposed to do this since the blades are passing over the pickup so quickly.

4. Grounds in general.

I have two ground running off the engine, the battery ground running to the engine, and a ground running of the - battery terminal to the chassis

5. Spark Plugs.

-I have the plugs gapped at .050 as per MSDs recommendation. My engine has 10.25:1 compression ratio.


So, at this point, Im starting to think that the magnetic pickup is faulty. I would consider other possibilities, but since the car was running before and now is not....

I could replace the battery, but I hate to waste money when it is not necessary.

Is there anything else that i should check before ordering a new magnetic pickup?

Comments, criticism, ideas, thoughts?

Thanks!

I had tolerated points ignition for years then gave up and went to an MSD pro-billet ready to run (at least for a while) distributor. Although it wasn't necessary I hooked up an MSD 6A with the new distributor. Ran great for three weeks or so the the engine died about a mile from the house. It would restart, but only for a few seconds then die. Auto Zone replaced it with a new one, but I feel the need to carry a spare magnetic pick-up with me. Complaints aside it's a great improvement.

The magnetic pickup failed in mind as well....O"Reilly Auto Parts had one in stock, $25. Part # 84661.

Remove a spark plug and with it inserted into its boot crank it over a time or two (trying to avoid it starting) and see if it sparks.

I am almost certain that is the problem, so i am going to go ahead and order a new one today from summit. Unfortunately, nobody locally has the part in stock.

I just went through this last week. It failed slowly, so each time it got harder and harder to start. Finally nothing. Replaced the Mag pickup and runs like a top. Gap it at about .024. I believe the instructions say between.018 and .034. Hard to do without removing the dist. but it can be done. Two bolts, some silicone gasket cement and some 11 underneath it. Hope it works. good thread on this under ignition, "no spark..help"

The MSD Magnetic Pickup was at fault, even though the OHMs read within the specified range.. Ill be calling MSD tomorrow to ask for a refund on the purchase of the new pickup. I changed the pickup out, removed the spark plugs and dried them off, blew out the cylinders with air, pumped a couple of shots of oil in the spark plug holes because the cylinders had been rinsed down with a ton of fuel, popped the plugs back in, realigned the cap, and vroom vroom. She's a mean machine!!! I have never seen a car rock back and forth like this one does at idle. I have a water leak at the water pump and oil is really leaking out of the drain plug and splattering out of the dipstick union, but those are small things that i can address tomorrow. I am just excited that it runs and sounds healthy.

Video, man, we need video!!!

Glad you got your main issue worked out. The others are minor in comparison.

Mark

Bars leak will take care of the water pump. Oil is oil, there always seems to be a leak somewhere on these cars. I basically gave up on trying to stop the oil leaks compleately. A couple drops does not bother me anymore.

Yeah, just a dynamic oil change!

You sure it's the water pump leaking? Some of the timing cover cover and water pump bolts hit water on an FE. Unless you put thread sealant on those bolts, you will get a little trickle.