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Ok here when I got the car 73 mach 351c it would only start by turning the key on and jumping the solenoid but i had to tap the solenoid with it jumped it would start and run good ,, so I thought maybe the neutral safety switch is bad and the solenoid so I changed the solenoid and now nothing ,,Whats the next step of do I take a ste



p back

 
If it won't turn over by jumping the solenoid try direct battery power to the cable going to the starter but just briefly to see if the starter actually engages

If nothing you've either got a loose connection especially at the starter or a burnt out starter motor

 
If it won't turn over by jumping the solenoid try direct battery power to the cable going to the starter but just briefly to see if the starter actually engages

If nothing you've either got a loose connection especially at the starter or a burnt out starter motor
I now jumped the small stud on solenoid (toward the front) to the big stud (toward the front) and started turns but engine wont run

 
If it won't turn over by jumping the solenoid try direct battery power to the cable going to the starter but just briefly to see if the starter actually engages

If nothing you've either got a loose connection especially at the starter or a burnt out starter motor
I now jumped the small stud on solenoid (toward the front) to the big stud (toward the front) and started turns but engine wont run it still won't do anything touching the two small studs together ??????

 
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You have the two wires reversed on the side of the starter solenoid.

 
lets make sure wires are correct. now looking at the sol pic.. left is "plus" battery, #2 wire (SMALL) is from ign sw start, #3 (small)is 12v to dizzy, right large goes to starter. first test as mentioned by a jumper from battery + to the right large wire to see if starter turns motor over (yes/no?). if yes then next is the left small wire should be 12v with key in start mode. do that and post results

 
fixed your replies Bat, don't type inside the quote box, makes it tough to read.

Hard to see in the pic, but I agree with Midlife, your solenoid wires are reversed.

Red w/light blue stripe to front small post

Red w/light green stripe to rear small post

 
Once you get the wires correct on the solenoid you still either have to turn ignition switch on or run a hot wire from battery to coil for the car to start by jumping the solenoid. If it has sat long time gas if probably bad and should be drained.

For sure do not pour gas in carb or you might burn car and garage down. If you need to squirt some gas in take an old plastic water bottle and cut a slit in the middle of the lid with a razor blade. This will allow a small squirt and no hole for a backfire to go into and set gas can on fire. Always have a fire extinguisher handy and 5 gallon bucket of water is also a good idea.

 
Once you get the wires correct on the solenoid you still either have to turn ignition switch on or run a hot wire from battery to coil for the car to start by jumping the solenoid. If it has sat long time gas if probably bad and should be drained.

For sure do not pour gas in carb or you might burn car and garage down. If you need to squirt some gas in take an old plastic water bottle and cut a slit in the middle of the lid with a razor blade. This will allow a small squirt and no hole for a backfire to go into and set gas can on fire. Always have a fire extinguisher handy and 5 gallon bucket of water is also a good idea.
I got all the safety stuff ..when I turn the key ignition switch it



 sticks on start (replacing the ign switch might not be a bad idea)I did switch the two small studs (Heres a pic ) turned the key car started and ran good only once then its back to jumping two front studs(one big one small)car starts runs good as long as I keep the jump on but I can't do that cause the starter keeps running car shuts off when I take jumper off..,,,,wires were on wrong before I got the car so when I put a new solenoid on wires went on the same way (Wrong) I think I made it to first base im going to take a break till later tonight ,,I cant say enough about the great help here its over the top but ill get back on that later

 
There's a problem in the wiring from your ignition switch to the coil. How do I know that? When you jumper the battery to the S terminal, the starter solenoid also puts out full battery voltage to the coil, bypassing much of the ignition to coil wiring, not not all. The infamous pink resistor wire, located in the underdash harness, lowers the voltage from the ignition switch to the coil from full battery voltage to 9V or so. If the voltage is much below that for whatever reason, the engine will not run well. Since it runs good with full battery voltage, that seems to isolate the problem primarily in the underdash harness or the connector to the headlight harness, or from that connector to the engine gauge feed plug near the firewall. That's where the junction is from the I terminal on the starter solenoid to the main coil line is joined (bypassed).

 
There's a problem in the wiring from your ignition switch to the coil.  How do I know that?  When you jumper the battery to the S terminal, the starter solenoid also puts out full battery voltage to the coil, bypassing much of the ignition to coil wiring, not not all.  The infamous pink resistor wire, located in the underdash harness, lowers the voltage from the ignition switch to the coil from full battery voltage to 9V or so.  If the voltage is much below that for whatever reason, the engine will not run well.  Since it runs good with full battery voltage, that seems to isolate the problem primarily in the underdash harness or the connector to the headlight harness, or from that connector to the engine gauge feed plug near the firewall.  That's where the junction is from the I terminal on the starter solenoid to the main coil line is joined (bypassed).
This is good stuff a lot for me to trace down Motor does run great never been raced all stock ,,im going to start with a new key swtch since its hard to turn and stays stuck in the start position hard to return to off...ill start their

then ill follow all this info step by step thanks so much every body ...im here to stay...

 
lets make sure wires are correct. now looking at the sol pic.. left is "plus" battery, #2 wire (SMALL) is from ign sw start, #3 (small)is 12v to dizzy, right large goes to starter. first test as mentioned by a jumper from battery + to the right large wire to see if starter turns motor over (yes/no?). if yes then next is the left small wire should be 12v with key in start mode. do that and post results
Starter does turn when jumping two big terminals on the solenoid

 
Ok ,,,I got another problem key switch is messed up key come out and still can turn it NAPA says I need to know if the switch was made before 5/14/1973 or after any info on this ,,,I hate to ask you guys have been pouring in info (when in done I hope to know this car inside out



 
You'll need to get you car's build date off the door sticker.

The tumbler pins are probably gummed up in the lock. Did you try any penetrating oil, to see if they would free up?

That is just the lock, the electrical switch portion is on top of the steering column, under the dash.

 
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You can also pull the lock out and take it to a locksmith, see if they can repair it. If you want your new lock key to match the door locks, the tumbler pins in the new lock will have to be changed to match your old key. Or, you can get a complete lock set and change your door locks, too.

 
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OH a big OH ill have to back up on this job I took the wheel off and started to take the lock out but couldn't so ill put everything back(not a problem) and change the switch Thanks for that Don the lock and keys thing doesn't matter to me ,,I just have to figure out how to remove the switch,,

 
Don't forget to disconnect the battery before tackling removing the ignition switch!

 
I found a new problem just like Midlife said connector under the dash looks like burt wires ,,,the yellow and red wires are from an alarm system the pass owner put in I did remove it ill remove the wires too soon ,,could this connector be to the starter switch? im going to get in to fixing this too I hope this will fix the problem (ill put changing the switch on hold for now



 
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