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.
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!