Electrical , Not cranking by key

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Kent mosby

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This is a non-oem setup. 1973 scamp with RB, internal voltage regulator, no ballast resisitor and hyperspark ignition coil and distributor. The issue is that when I turn the key to start, nothing happens.

I have verified that I get 12.65 v to the yellow wire going to the starter relay when key is set to start, no volts for off and run positions.

When I jumper the starter relay, the motor turns over without issue.

This leads me to believe that either the starter relay is not working correctly, either broken or not hooked up correctly. OR that the neutral safety switch for the 727 is not working correctly.
Correct????

Can I ground the starter relay, bypassing the neutral safety switch, just to test the starter relay??? trying to eliminate one factor.. There is no driveshaft, so not a safety issue of starting in gear. This seems easy to try but I don't want to break something.

How do you test the neutral safety switch?

Am I missing something?
 
Neutral switch is most likely your problem. You can ground that terminal at the relay and see if she starts. If that fixes it, then your shift linkage may need some adjustment. Do not start w/o a driveshaft.
 
^^As above^^ The functional path through the relay is yellow wire from key..........through the bulkhead........to one of two flag terminals on starter relay...........through the coil..........out the second flag terminal.........and down to the NSS switch (auto) or to clutch switch (stick) and to ground.

Clip a meter on the wire going to the NSS that is back probe it at the starter relay without disconnecting. Twist the key and if you have voltage, the switch is not grounding. Most likely cause is out of adjustment linkage

Try holding the key to "start" and wiggling the shifter from park to neutral and back and see if you get a "click" or partial "try to crank."
 
Did you measure that voltage with the yellow wire disconnected? "it might be" that you have a poor connection........either bad ignition switch, poor terminal at switch connector, or at bulkhead connector,
 
Thanks for the help. Well, now that I see the path,(thanks again) I may see the problem. I do not have the coil hooked up at all. Also the transmission has no shifter yet. I just pulled the lever all the way back by hand. To check, I did ground the starter relay and it cranks. So it must be in the path to the NSS it up to the SR. Time to hook up the coil. Also checked the voltage at the SR. During cranking, there is 12v at the wire coming from the NSS to the SR.
 
When I ground the center wire of the NSS connector after removing it from the transmission, I can get cranking. I have a new NSS coming from napa in a couple hours. In the meanwhile, Is it possible that there is an open ground in the seatbelt wiring that could prevent cranking? The seatbelts are not installed.
 
Check wire continuity from NSS to starter relay. The connector at the NSS can be finicky.

Maybe make a jump wire to test from NSS to relay.
 
crackedback said:
Check wire continuity from NSS to starter relay. The connector at the NSS can be finicky.

Maybe make a jump wire to test from NSS to relay.
Click to expand...

I grounded the center wire of this connector while it was plugged into the starter relay and got cranking. I “assume” that means the wire is good. Brand new connector
FE50B8C9-4E7B-4E76-A2CD-1874E341AB44.jpeg
 
Then it's either bad NSS or out of adjustment, or problem in the "rooster comb" internally

Make certain switch has the correct gasket (I can't help you there) and is properly tightened

If you are shifting by hand it might not be engaged. Try N instead. Your mention of the seat belt deal interupts the path of the yellow wire on the road to the starter relay, but that only affects 74 cars, and they have the infamouns "reset" box under the hood
 
It was the NNS. The connector that touches the rooster comb was not extended. Problem solved. Thanks for the help.
E561EFD0-A53C-4687-9FBE-0AAA5041F5EB.jpeg
 
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