acavagnaro

Hello and thanks in advance to any assistance you guys can provide. I have a '69 442 with a factory style starter (AC Delco) and factory style wiring harnesses. Starts and runs perfect with the factory style mechanical distributor.
I recently installed an HEI and have been unable to get the car to run. The starter turns over as it should when the ignition is in the 'on' position and the engine immediately tries to fire but then dies. It seems like the 12V supply to the HEI is being cut as soon as the ignition goes from 'on' to 'run'.

The stock style solenoid has the large threaded stud for the + power cable from the battery and two smaller threaded studs, "R" and "S". I have the batter cable on the proper large stud. I've left the factory harness connected to the "S" terminal which should be the ignition.
What I changed: I disconnected the factory wire on the "R" side of the solenoid and also have it disconnected at the top of the engine (where the original coil used to be). I've run a wire from the "BATT" terminal on the HEI directly to the "R" post on the solenoid. For what it's worth, I also connected the tach lead from the HEI to the power wire of the tach (aftermarket).
If I understand the circuit properly, I should be getting 12V directly to the HEI when the ignition is in the 'on' and 'run' positions but that is apparently not what's happening. As I said, it appears to get 12V when the ignition is 'on' but then loses it when it goes to 'run'. Any ideas on what may be happening here?

FMB42

Did you bypass the point system ballast resistor?

m371961

The ignition to the HEI must come from a 12 volt source that is hot when the key is in run. The starter to coil only provides 12 volts when the key is turned to start.
You have to remove the original resister wire that comes from the ignition switch and replace it.
Do a search on HEI conversion.

oldcutlass

This should help:

acavagnaro

Thanks, guys. Put a meter on it last night and confirmed I'm only getting 9V at the HEI with key in "start" position. Drops to almost zero with key in "on" position. Interesting because the ballast resistor is completely out of the circuit. This tells me the Delco solenoid must be stepping the voltage down from 12 to 9.
I'll reroute the HEI power lead to the "IGN" blade terminal at the fuse block. One last question; I currently have my aftermarket tach power lead plugged into the "IGN" blade. If I keep this at "IGN" along with the HEI lead will it draw too much current and affect the HEI operation? I wouldn't think so but I'd appreciate any comments. The tach is a mid-80's vintage Sun Super Tach II, nothing fancy.

oldcutlass

The tach goes to the other lead on the cap. The 12v goes to the positive side of the coil and the tach is the negative.

joe_padavano

Not by design. This is probably telling you that the solenoid terminals are heavily pitted and in need of replacement.

Run to Rund

You can also look for a wire that is hot on start and run. The orange lead to the bellcrank on 66-7 automatics is one such wire.

acavagnaro

This should be the last word on this topic and, hopefully, what I've learned will help others in the future. Thanks again to the great advice and comments from other members.
I had the HEI wiring wrong. I now understand the starter wiring and it makes sense the car wouldn't run. The factory harness ignition wire should connect to the "S" terminal as intended. The battery positive lead should also connect to the solenoid.
The HEI "BATT" terminal goes to a 12V source that is 'hot' when the ignition is in 'start' and also 'run' (when the engine is running). I followed the advice above and tapped into the "IGN" blade in the fuse box. There is also a tach lead on the HEI that can be used to provide a tach signal (not power).
The Sun tach I have has 4 leads; power (12V ignition source), tach signal (either from a traditional coil or now the HEI tach lead), ground and a light source (headlamp fuse in fuse box so tach light comes on when dash lights come on).
Pretty simple, really. With a full battery charge I get 9V cranking ('start') at the "IGN" terminal and 12V on 'run'. Engine fires right up and runs great.

oldcutlass

Glad you got it going.