View Full Version : No spark!

07-30-2003, 08:02 PM
I have a '71 Plymouth Scamp, and just finished a complete rebuild. New engine, wiring, everything. I'm running an MSD Digitial 6 Plus, Blaster HVC coil, Billet distributor & MSD wires. A few days ago the engine was fired for the first time. It started without trouble, and I immediately took the engine to 2500RPM to break in the cam. It ran for about 10 mintues, and I shut it down to do the usual initial start up inspection. I let it cool, and then restarted. It fired up again without any problem...and ran for 5 minutes, then died. I have not been able to start it since then.

Connections are as follows:
Heavy red: 12V+ from battery. Tested with a multimeter - less than .01V drop at the connection.
Heavy black: Grounded to engine block.
Thin red: Connected to original + coil wire (per instructions). Tested, and has 12V when the key is in run & start.
Orange/Thin black: Coil + / Coil -
Green/Purple: Distributor pickup
White: Not connected
Pink: Not connected
Light Blue: Not connected
Green loop: Cut and sealed

I've performed testing per the troubleshooting in the Digital 6 manual - I disconnected the pickup wires from the distributor, disconnected the coil wire from the dist cap and set 1/2 from ground (eng block), turned key to run, and jumped the green & purple wires - no spark when the jump is broken. I've tried several times.

Also, the red LED on the Digital 6 is lit solid when the switch is in the run position. If I turn it to start, the LED blinks rapidly as if it is detecting the pulse from the pickup in the distributor.

At this point, I figure it is either the coil or the box. I do not have another coil handy to test - what should I do?

Thanks in advance!

07-31-2003, 09:20 AM
Spoke with MSD tech support on the phone....no reply needed here. Thanks!

07-31-2003, 09:33 AM
Disconnect all wires going to the coil and then check the primary resistance between the coil positive (+) and Coil negative (-) terminals. The resistance should read 0.02 ohms when cold. Next, check the secondary resistance between the coil positive (+) terminal and the high tension terminal (coil wire attachment point). Repeat the same check using the coil negative (-) terminal. The secondary resistance should be approximately 1.38K ohms.

MSD Tech1

07-31-2003, 10:42 AM
Thanks, I will try that. We just picked up an 8253 to replace this one if it turns out bad....

I'll post the results here as well.

Thanks again,

07-31-2003, 05:28 PM

MSD Tech1

07-31-2003, 07:09 PM
The original coil (HVC 8252) was bad. I checked the primary and secondary resistance - primary was 0.00 and secondary was 1.237. At first I thought it may still be in spec, but we tried the new coil (Blaster HVCII 8253) anyway. The spark test netted positive results...each time I removed the pick-up jumper, we had MASSIVE spark to ground. Scared me actually!

Needless to say, it fired right up. I ran it for 10 minutes and blipped the throttle a few times. Very crisp response and smooth, quick revs. I'm happy to say the least. :)

Thanks yet again for all the help!

T Monte

08-01-2003, 10:17 AM
Very good. Glad to be of help.

MSD Tech1