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Starter Switch Woes -- A Potential Culpirt?

GA72TR6

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The hand break theory sounds intriguing. Though I’m unable to replicate that specific scenario, I’ve still potentially have a short somewhere (unless the information at the end of this post under POTENTIAL SUSPECT is the true culprit here).

I took some voltage measurements this evening with everything hooked up (except the starter cable - I’m tired of getting shocked!). In the following, S = solenoid, I = red/white ignition wire at the solenoid, C = coil wire at the solenoid:

key @ crank - S engages, I=11.8, C=12.1
key @ on – S stays engaged, I=8.7, C=12.1
key @ accessory – S stays engaged, I=5.5, C=12.1
key @ off – S stays engaged, I=6.0, C=12.1

So, “S,” stays engaged at every key setting after it’s been initially engaged by “I.” “C” always has ~12V running to it despite the key’s position, and, although it drops, “I” also shows voltage when it’s connected to S despite the key position. Through the key sequence, “S” never disengages. I disconnected “I” from “S” and “S” disengages.

Then I ran another test with “I” disconnected from “S” to test the starter switch independent of the solenoid:

Key @ crank - I=12.1, C=6.3
key @ on - I=11.8, C=6.3
key @ accessory - I=0, C=0
key @ off – I=0, C=0

So, the coil is getting charge somewhere even when the ignition wire is disengaged from the solenoid. I assume this should not be the case. Note that in this second sequence, “S” does not engage at all.

POTENTIAL SUSPECT
While referencing the diagrams and a catalog listing for a new distributor, I noticed there are two distributors (Moss Motors) for the 1500 Midget: a C.E.I. distributor that has a single lead from distributor to the coil and an Opus distributor that shows three wires connecting - via a junction box - the distributor to the coil (one wire) and ignition switch (two wires, one via a distributor resistor). My car has only one wire from the coil to the distributor, so I’ve assumed that I have the C.E.I. distributor.

30 minutes ago, however, I found a disconnected junction box coming out of the original ignition switch wire bundle with three wires connected to it. This looked suspicious, so upon closer examination of the wiring diagram, I found they match the colors of the THREE wires going into the distributor, connected via a similar junction box to three wires in the ignition switch bundle….like the 3-wire Opus distributor connection.

But, again, this three-wire junction box is not connected to anything in my current setup – only a single wire connects the distributor and coil. Given the rigged starter button installed by a PO (the replacement of which is the start of all this mess!!!), it wouldn’t surprise me if the PO at some point replaced the distributor (3-wire coil/switch connection) with the wrong one (1-wire coil connection) - one that would not work with my ignition switch, and that’s why he installed the starter switch bypass button in the first place.

Does that sound like a potential cause? If that gives anybody an “ah ha!,” I’ll flat-bed this thing to the import shop and let them replace the distributor and properly connect it, if necessary, or otherwise track down my wiring short.
 
The distributer is probably not your problem. It sounds like a PO repalced the Opus system with a points or Petronix system or even a CEI system. The Opus systems were awful and few, if any, have survived.

If everything worked right before you installed the new switch, then the evidence points to the switch (sorry).

I am looking at the diagram, and I think I have figured out a possible test that could determine if the problem is in the switch or someplace else. Disconnect the brown wire from the solenoid and check for power at the coil. If you have power, the short is someplace in your wiring harness, and will have to be painfully traced. If you do not have power, odds are the short is in your switch. If so, this is good and bad news. The bad news is the switch will have to be checked and possibly rewired or replaced. The good news is that the short is not somewhere in your harness. That can be a real nightmare!
 
/ubbthreads/images/graemlins/iagree.gif The distributor wiring is probably not the problem. The Opus distributor had 3 wires; 12 volts from the ignition, 1 wire from the coil, and 12 volts by way of a resistor mounted on the pedal box. A points distributor only needs the one from the coil. A Pertronix would use two, as I did since my Opus box was kaput when I got my car.
 
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