<VV> At Wit's End with HEI Ignition

[JVHRoberts at aol.com]

OK, here's a few more:
1; Is the HEI module and the coil properly grounded? Remember, the HEI  
module's output transistor switches the negative side of the coil to ground,  just 
like the points do, although the timing is rather a lot fancier. 
2. With the ignition on, and the cap off, do you get a spark from the coil  
when a screwdriver is is passed over the end of the pickup, with the reluctor  
nowhere near it?
3. With the engine cranking, and using a DVM, do you get an AC voltage from  
the pickup assembly?
4. With an ammeter in series with the + feed to the thing, does it draw  
current when the engine is cranked? This would be a sure fire indication that  the 
ground path is open.
 
The fact you can get the coil to fire means the coil is good. The fact that  
the HEI system can't ground it means either the module's ground is  open, the 
module is bad, or the pickup is failing to trigger the thing. The  coil is 
normally deenergized on these things if there's no signal.
 
In a message dated 3/25/05 5:11:13 PM Eastern Standard Time,  
goofyroo at excite.com writes:

Some of  y'all have responded to my questions about the sudden HEI ignition 
failure in  my '63 convertible.  This is the Dale hybrid system that's served 
me fine  for six years.  (Dale hasn't answered calls yesterday and  today.)

I've tried replacing some parts and diagnosing others thusly,  still no spark:

- New GM brain box
- New Chrysler pick-up; wires are  good
- Tested a known good coil in place of 6-year-old  Flamethrower
- Ohms check out OK
- Flamethrower produces a  spark at the output when the - terminal is 
grounded, then released
- Rotor  turns with engine
- Engine ground is good
- Ran 12V directly to +  terminal of coil

None of this gets a spark out of the ignition wires,  or even out of the coil 
wire when it's held just a bit off the  contact.

All that's left to replace are the brass-contact cap and  rotor.  I cleaned 
them up, and can't imagine how one could fail  suddently.  I even tested the 
rotor to ensure it is contacting the center  post.

I'm at wit's end with this.  Anything I haven't  checked?

Michael Smith
Dallas