Something weird going on

[70chall440]

I am using a Blaster II coil and it seems to work ok.

[734406pk]

I am using a Blaster II coil and it seems to work ok.

Me too, no problems FWIW.

[cudabob496]

OK, after bugging MSD 4 more times, they sent me out to the car in the garage,
and on the phone, we diagnosed the issue. When all is energized, I tapped the white
wire (which is not in use) to ground, and got a spark, so they say the coil is good.
Looking for a spark between the violet and green wires coming from the MSD box, and going to
the dist, I shorted them looking for a spark, and got none.  MSD now believes, since no spark observed,
the magnetic pickup circuitry in the box is bad, so the box is going back to MSD, even
though I just got it back, having been told everything was good. Wah!!

[HP_Cuda]

Wait a min, can't the magnetic pickup in the distrib also be the problem?

[70chall440]

Man that sucks, but you are making some progress it seems.

[cudabob496]

Wait a min, can't the magnetic pickup in the distrib also be the problem?

replaced that, but the MSD test on the 6AL box is done with the dist disconnected.

[73440]

I am away from the 6AL and distributor for a few days and could send on Tues if you need them.

[cudabob496]

I am away from the 6AL and distributor for a few days and could send on Tues if you need them.

thanks kindly! Let me see if MSD can fix it this time.

[HP_Cuda]

Sucks you have to send it back again!

 

replaced that, but the MSD test on the 6AL box is done with the dist disconnected.

[cudabob496]

Sucks you have to send it back again!

 

new twist, when we decided coil was good, it was due to me touching white wire to ground.
But there is also a white wire from the timing control unit. That is the one I touched to ground, by mistake.
So, I just mailed in 6AL box and coil. If both come back working, then suspecting the timing control
unit may be the culprit.

[734406pk]

I hope you can find the cause soon, you certainly deserve a break!!

[Cudakiller70]

I hope you can find the cause soon, you certainly deserve a break!!

  or it could turn into the never ending thread.

[cudabob496]

ya, been trying to solve for 4 months. Have rebuilt carb, put in new intake manifold, new
mag pickup in distributor.  New plugs, checked plug wires, etc. Looking like problem is in
6AL box or MSD timing controller. Will be interesting to see what MSD says next.

[cudabob496]

If you look at the diagram at the bottom of page 12, that's what
I'm dealing with. I just realized that when I hooked it up this time, I
may not have had 12v red wire from the timing unit energized. So if the box comes
back with them saying it is working correctly, then maybe it wasn't working
correctly this last time because I had it mis-wired. If that's the case, then the
real problem may have been the bad ground on the box, which they discovered
the first time I sent the box in.  Working under the dash with all these wires does
not help, but I may have messed up.

https://www.jegs.com/InstallationInstructions/100/121/121-6420.pdf

[HP_Cuda]

You have timing control as well?

Hate to throw another monkey wrench but your timing control could also be giving you problems. Didn't the tech's walk you through troubleshooting the timing control as well?