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tluz
06-29-2014, 12:41 PM
Hi, Guys,

Haven't posted for a while. The Avanti has me depressed.

Subject is a rebuilt 1963 Avanti with Chrysler HEI ignition. I have had numerous electrical issues and tried some extracurricular stuff, but basically it's a stock R-1 Stude with a Dave Thibeault electronic box. Has the rebuilt Prestolite alternator, a new Jon Myer voltage regulator, new coil, plug wires, etc. The car was running for a brief period last summer but has encountered problems since.

At one point over the winter something happened and I melted the red wire going to the ammeter. I don't yet know what caused the problem. Something was carrying current to ground even when the ignition switch was off. I replaced the ammeter wires in and out with thicker gauge wires. i disconnected all electrical components and dissected the wiring harness in an effort to locate the offending wire. This was not easy and necessitated loosening the dashboard. Evidence pointed to a multiple-spliced, black ground wire that ran, among other places, to the BAT terminal on the VR. that said, there was no visible damage to this hydra of a wire. Maybe it was just in the wrong place at the wrong time.

I thought I would just reconnect the starting circuit and proceed in a methodical way, component by component, until I located the problem. This is where I hit a snag.

The ignition is wired per the electrical diagram in the shop manual, modified by Jon Myer's instructions for the HEI. The ACC wire is not connected because i am not using the accessories yet; the plan was to add them in one at a time after I knew the starting circuit was good.

Once I disconnected everything, reconnected only the starting system, double-checked all of the connections, and turned the key, the engine turned over enthusiastically. Joy swelled within me at my achievement. The plan was working and I was bringing the car back to life.

Emotions, as we all know, are short-lived. I turned off the key and the engine continued to crank. I removed the key and the engine continued to crank. This was a bit disconcerting. I ran to the battery and disconnected the negative cable. This stopped the cranking.

After calming down and doing some thinking, I concluded that this is an easy one. The ignition switch has to be stuck in the closed position. Replace the ignition switch and problem will be solved.

So I did that. Hooked up the brand-new Studebaker International ignition switch, reconnected the battery and hit the key. Same enthusiastic cranking, even with the switch off and the key removed.

So now I'm perplexed. Why is current flowing even with the brand-new ignition switch off?

The only component connected are:

Battery -- Solenoid -- Ammeter -- voltage regulator -- ignition switch -- HEI module -- starter motor.

Any ideas?

Thanks, as always,

Tom

Warren Webb
06-29-2014, 01:00 PM
Sounds to me that the solenoid is stuck. Disconnect the center push on connector on the ignition switch. Disconnect the rear push on connector on the solenoid, then connect the battery and test. If the starter still spins everything else has been eliminated except the solenoid-replace.

bezhawk
06-29-2014, 01:04 PM
The black wire to the VR is not the ground! All grounds are white on an Avanti harness. Or more correctly were when new. How are you triggering the start terminal on the solenoid? That would be the place to look as it continues to be enrgized even when you turn the key off.

gordr
06-29-2014, 03:09 PM
Somehow, you have set up a "latching" relay circuit. A relay (and the starter solenoid is one) is said to "latch" when its own output is fed back to its input, causing it to lock in until power is removed. I would look very closely at the two small wires, and where they go. If the "I" terminal is somehow connected to the "S" terminal, this will happen. Also make sure that no wires, other than the starter cable, are connected to the stud supplying the starter.

If it's a Chrysler product electronic ignition, it's not an HEI. That's a GM brand, and describes the system with the very large distributor cap, and all the parts incorporated into the distributor, coil, module, pickup, etc. HEI doesn't need a 12 volt boost when cranking. The Chrysler ones did, at least some of them, that used the dual ballast resistor. Check with Dave Thibeault, he should know how it is supposed to be wired.

Try starting it with the wire off the the "I" terminal. If that "solves" your problem, you know where to look.

tluz
06-29-2014, 06:02 PM
Will do, thanks, guys.

allstudedude
07-01-2014, 04:31 AM
Hi Tom,

Did you get the problem fixed? What was it? My money was with Warren Webb on a stuck solenoid.

Phil.

tluz
07-05-2014, 03:39 PM
hi, Phil,

Just noodling it out today.

Doing it precisely Warren's way, there's no power through the ignition switch. That red/white wire carries juice through the ignition switch to the solenoid. No connection, no juice.

I took the idea, though, and isolated the starting circuit by disconnecting the wires to the ignition module and system, including the green/white from the forward solenoid terminal to the coil. The only components connected were battery, solenoid, ammeter, ignition switch, starter.

This time, after connecting the battery and hitting the key, the starter spun when it was supposed to and turned off when it was supposed to. It looks like the starting system, including the solenoid, is clean. So now suspicion swings directly to the ignition system and its wiring, and points to Gord's theory of a latching relay circuit.

If I have this right, there are three relay circuits that could pass juice between the S and I terminals: the solenoid, the ignition switch, and the electronic ignition module. The solenoid seems innocent unless the green/black wire to the distributor output of the coil is involved. That leaves the wiring connecting the ignition switch and the Chrysler unit. Both are new, so while we cannot entirely discount the possibility of a fault in one or both, more likely the problem lies in how I connected them.

So help me think this through, please? how would I figure out what's feeding power back to the solenoid, if that's in fact what's happening?

Thanks again for all of your support. You make me feel like this project is possible.

Xcalibur
07-05-2014, 06:03 PM
Sorry I didn't have time to read more than your intro, but just a comment none the less before I have to run. Don't assume "new" parts equal functional parts. Sometimes a bad one slips through... and can drive ya nuts. All the best.

StudeRich
07-06-2014, 12:13 AM
You may have figured it out. Most Electronic Ignition systems do not require 8-9 Volts for "Running" since they run on 12 Volts all the time and have no Points to "Burn".
Therefore you can disconnect that Green & White wire from the "Ign" Terminal of the Solenoid that gives the Coil 12 Volts on start.

Also, if the Module instructions say to bi-pass the Resister on the Coil, make sure you did.

tluz
07-06-2014, 08:50 PM
Looks like the culprit was the green/black wire from coil to solenoid. I reconnected the wire from the ignition center stud to the ecu but did not reconnect the green/black. Engine cranked and stopped the way it should.

Next step is the slow process of reconnection and testing or all electrical components.

Thank you all for your expertise and willingness to help. Someday at least one of you will come to the NYC area and I hope you will accept the lunch/dinner/coupla beers I am hoping to buy you.

Best,

Tom