Hei conversion Intermittent start?

jimmyray said
The cap is most likely not the issue. The HEI voltage will jump across it.

Check 3 things and let us know:

1. Unplug the wire from the distributor to the HEI module, and connect your multi-meter to the two wire, in DC millivolt mode (200 mV or less). Crank the engine, and see if the multimeter readout changes. You should get abounce of between -60 and 60 milliVolts. This will confirm you have a good tach signal to the HEI.

2. Confirm you have voltage to the HEI when the switch is in the "run" position, by checking the voltage directly from the HEI blades, without unplugging anything. This voltage should be identical (+-0.1 volts) to the battery voltage across the battery posts.

3. Check the voltage to the HEI when the engine is cranking, voltage directly from the HEI blades, without unplugging anything. This should exceed 11 volts, and be identical (+-0.1 volts) to the battery voltage across the battery posts while cranking.

If all 3 of these check out, then we have effectively eliminated the wiring and voltage as problems.

Triple check the wiring polarity from the distributor to the HEI. Even if the wiring is correct, swap the wiring polarity (switch the two wires top to bottom). Try firing it again, just to see.

What is left?
Coil
Module
Coil wire to distributor

1. i unplugged the dist. plug and connected two prongs to the plug that goes to the distributor, set the meter to 200mv as shown in your picture(luckily, we have the same cheap meter) and turned over the engine. It didnt go over 0.xx(less than .2-3ish). Sorry no pics of it, working alone with some dead time before my first call.

2. With the ignition in the run position put a prong on the "B" blade(red power wire going to my relay) and the other prong on the C blade(black wire goes to neg. on coil). Set to DCV-20. It gave me 0.34v. However, putting one prong to a ground and measuring the C & B blades individually i got readings that were within .1 of the battery measurement.

3. A little hard due to #2 and a low battery(i guess i'll be seeing the parts store for charge number 5. In run battery shows 9.12v, cranking it dips to 8.9 or so. Individual blade measurement(like described in #2) shows 8.7x at each blade when cranking.

Everything connected in the tests minus the dist. plug for #1

PS: i have that plastic shielding, I bought 7ft of it to get rid of the annoying harness tape. I just havent put it on the firewall until i get the ignition finished.(which should hopefully explain why my firewall looks like a mess of wires)