Cranks over in the run position.

[mach71351c]

Well I'm stuck. My Mach 1 cranks over when key is in the run position. The first thing I thought starter solenoid. Replaced it, nope, not it. I tried adjusting the original ignition switch, with no luck. Ran out and bought a new ignition switch but it still cranks over when the key is in the run position and all the way to the crank position.
I do not have the neutral safety switch hooked up, would that have anything to do with it? I wouldn't think so.

Mike

 

[boilermaster]

mach71351c,
Red/Green ckt. 16 to I terminal of starter relay .
Red/Light Blue ckt 32A to S terminal of starter relay.
S terminal supply's voltage thru the neutral switch
I terminal provides voltage to the coil during cranking.
Make sure these push on terminals are not reversed.

 

[mach71351c]

Thanks boilermaster I have checked the push on terminals. I even had Jim sdstang bring his 73 by the house to make sure I had the wiring correct at the solenoid. Even went to my Cruse night and took pics other Mustangs to double check. I'm just stumped why it cranks over in the run position.

 

[Doug's 73 Mach1]

The ignition switch has a position where a lock pin is inserted so the switch can be adjusted to the correct position along the steering column. The ignition key also has to be in the right position when doing the adjustment. After installation/adjustment, then the lock pin is removed.
From the symptom you have, the switch could be too close to the steering wheel end of the column. As I recall, there is a bit of slop/play in the mechanical connections between the ignition key cylinder and the ignition switch. If all the slop/play is absorbed by pushing the ignition switch up the column toward the steering wheel, that might create the condition where it can crank in the run position.
The ignition key cylinder is connected to a gear. That gear is meshed with a gear tooth "rack" which has a wire rod connected to it that goes down to the ignition switch. That series of mechanical connections is what typically has some slop/play in it.
Adjusting the ignition switch to neutral "slop". (equal amount of slop toward and away from the ignition key) or all the way further down the column might do the trick.

 

[Hemikiller]

Well I'm stuck. My Mach 1 cranks over when key is in the run position. The first thing I thought starter solenoid. Replaced it, nope, not it. I tried adjusting the original ignition switch, with no luck. Ran out and bought a new ignition switch but it still cranks over when the key is in the run position and all the way to the crank position.
I do not have the neutral safety switch hooked up, would that have anything to do with it? I wouldn't think so.

Mike

If you bypassed it incorrectly, yes. The NSS has two circuits, one for the starter, the other for reverse lights. To bypass the NSS function, you need to jump the two Red w/Lt Blue stripe wires at the NSS connector by the firewall. If you accidentally jumped the White w/Pink stripe wire (reverse light power to switch) to the Red w/Lt Blue stripe wire, it'll crank as soon as you turn the key.

 

[steves73]

Was anything else changed recently, or did this just happen?
I had the misfortune of my spare solenoid also being stuck on start. I don't know where I got it, but I thought the odds of both solenoids being stuck on was just silly. I took apart my whole steering column. Then I tried the solenoid out of my cougar and problem solved! When I take a bad part off now, I make sure it will never be mistaken for a spare.

 

[will e]

Have you checked the solenoid wires with a voltmeter?
Remove the small wire on the solenoid closest to the starter, this provides power to the coil while cranking. It won't hurt to leave it off while testing.

 

[mach71351c]

If you bypassed it incorrectly, yes. The NSS has two circuits, one for the starter, the other for reverse lights. To bypass the NSS function, you need to jump the two Red w/Lt Blue stripe wires at the NSS connector by the firewall. If you accidentally jumped the White w/Pink stripe wire (reverse light power to switch) to the Red w/Lt Blue stripe wire, it'll crank as soon as you turn the key.

Thanks Hemikiler. I haven't done anything with the NSS connector at the firewall. I remember when I was a kid installing a B&M shifter in my 71 Grande I had to add a jumper wire and wire the reverse lights to the shifter. Thinking I need to add the jumper wire anyway.

 

[Don C]

Had you worked on anything right before this problem started, or did it just happen by itself?

 

[mach71351c]

The ignition switch has a position where a lock pin is inserted so the switch can be adjusted to the correct position along the steering column. The ignition key also has to be in the right position when doing the adjustment. After installation/adjustment, then the lock pin is removed.
From the symptom you have, the switch could be too close to the steering wheel end of the column. As I recall, there is a bit of slop/play in the mechanical connections between the ignition key cylinder and the ignition switch. If all the slop/play is absorbed by pushing the ignition switch up the column toward the steering wheel, that might create the condition where it can crank in the run position.
The ignition key cylinder is connected to a gear. That gear is meshed with a gear tooth "rack" which has a wire rod connected to it that goes down to the ignition switch. That series of mechanical connections is what typically has some slop/play in it.
Adjusting the ignition switch to neutral "slop". (equal amount of slop toward and away from the ignition key) or all the way further down the column might do the trick.

Thanks Doug, The new ignition switch had pin in it. I installed it with the key in the lock potion then removed pin. I adjusted the original and the new switch up and down the adjustment slot. Even removing the switch and reinstalling the pin and checking with original nut marks on the original switch.

I will head for ignition cylinder for a over all look

 

[mach71351c]

Was anything else changed recently, or did this just happen?
I had the misfortune of my spare solenoid also being stuck on start. I don't know where I got it, but I thought the odds of both solenoids being stuck on was just silly. I took apart my whole steering column. Then I tried the solenoid out of my cougar and problem solved! When I take a bad part off now, I make sure it will never be mistaken for a spare.

Thanks steve73, I would call it the challenges of a ground up restoration. The 1st solenoid new from NPD, 2nd from auto zone. I was thinking of trying a 3rd.

 

[mach71351c]

Had you worked on anything right before this problem started, or did it just happen by itself?

Thanks Don, Yes a 11 year ground up restoration. I did remove the original ignition switch to paint the column.

 

[Doug's 73 Mach1]

Mike, another possibility is the Start (red-light blue) wire is shorted to the Run (red-light green) wire. You can check that with a continuity meter (ohm meter) at the R-LG wire at the ignition coil and the R-LB wire at the starter solenoid with the key in the off position. There should be no continuity.

Doug

 

[tony-muscle]

Thanks Doug, The new ignition switch had pin in it. I installed it with the key in the lock potion then removed pin. I adjusted the original and the new switch up and down the adjustment slot. Even removing the switch and reinstalling the pin and checking with original nut marks on the original switch.

I will head for ignition cylinder for a over all look

I had a similar issue in the past, but in the other direction. It just happens that the ignition gear could jump one of the gears on the steering drive, which could lead to what you are describing.

 

[mach71351c]

Mike, another possibility is the Start (red-light blue) wire is shorted to the Run (red-light green) wire. You can check that with a continuity meter (ohm meter) at the R-LG wire at the ignition coil and the R-LB wire at the starter solenoid with the key in the off position. There should be no continuity.

Doug

Thanks Doug, Sounds easy enough I will take a look.

 

[mach71351c]

I had a similar issue in the past, but in the other direction. It just happens that the ignition gear could jump one of the gears on the steering drive, which could lead to what you are describing.

Thanks Tony, I half suspected it had something to do ignition cylinder.

 

[boilermaster]

mach71351c,
Do you get the same issue with the old switch, leave it out of the column and plug it in and move the switch manually.

 

[mach71351c]

Got off work a little early and dove in. 1st I attached red with Lt blue wires at firewall connector. Remove power from the coil. Install solenoid #3. Removed ignition switch form steering column and tried it with out the key hooked up. Still turns over in the run position. Switched back to the original ignition switch for the hell of it. No change. So needless to say I'm still stuck.

 

[boilermaster]

mach71351c,
Find the Red/Lt Blue wire on the ignition switch connector and verify if you have voltage there (with the S terminal at the starter relay removed) and the key in the run position.
If things are as you have described the answer will be YES.
Now unplug the neutral switch connector, do you still have power at Red/Lt Blue at the ignition switch?.
if YES you have a short to power somewhere from the neutral switch to the ignition switch.
If NO , leave the neutral switch unplugged and recheck in the CRANK position.
If all is good (only power in CRANK) that part of the circuit is ok.
Now check for power at the neutral switch connector (still unplugged) find the terminal that is hot, only in the CRANK position, is that wire Red/Lt Blue ?
if, YES, is the corresponding wire in the harness also Red/Lt Blue ? , it should be.
Now do a continuity test from the unplugged Red/Lt Blue wire at the starter relay to the unplugged harness side of the neutral switch, if you have continuity, plug both ends back together, if you still have power in the RUN position, you have a short to power from the S connector at the starter relay to the neutral switch.