Ignition problem

[xfactor]

Hey All,

I was driving back to my office yesterday, the stereo started cutting out.
I parked and went in, came out and it wouldn't start. Tried jumping and found that the pos battery cable had came loose from the terminal clamp (more PO sh!t. Hooked it back up and it still won't start, I've got lights and all accessories but no ignition. It's a '73 302, C4, with a Crane fireball ignition and a Petronix Flame Thrower coil. I found a fuseible link from pos side of solenoid to harness and temporarily by passed it, still nothing. Any ideas where to look? Is there another fusible link somewhere?

Thanks
Ray

 

[70_Steve]

Need more information than "it won't start". Does the solenoid click? Does the starter turn the engine over? If so, have you checked for spark?

 

[xfactor]

Hey Steve,

Nothing, turn the key and it's like the battery is dead. I've got lights and wipers, etc. I'm thinking the pos battery cable shorted out on something? Is there a fuse for the ignition? I didn't see a slot for one in the fuse box.
Someone told me there might be another fusible link between the alternator and the solinoid. I was able to hot-wire it (wire from the coil to the pos battery cable) and cross over the solinoid and it runs. I'm not real good with troubleshooting electrical, thought maybe someone has already been through this and it might keep me from replacing the entire electrical system.

Thanks for your input,
Ray

 

[77broncoguy]

I'm trying to troubleshoot the exact same problem right now, going on day 3. :-X

I posted a couple of threads the other day, they may have some information that could help. Otherwise, if I get mine figured out, I'll pass on what I learn. I'm going to isolate the switch this morning.

Can the Voltage regulator go out overnight?

 

[70_Steve]

I hope you have a volt meter, or at least a 12volt test light!!!

Power for the lights does not go through the ignition switch. But power for the radio and wipers would, unless someone rewired things. Power to the ignition switch comes from the yellow wire on the back of the switch. If you have accessories with the switch at RUN or ACC then you have power to the switch, and the wire to the starter solenoid (32 - Red/Black tracer) is bad. You said, though, that when this problem first started, the radio was cutting out. Did the engine stumble at the same time?? That would indicate that the ignition switch was loosing power, because the coil gets its power through the ignition switch as well.

 

[xfactor]

Hey Steve,

I don't think the engine stumbled but it was a quick in and out on the stereo. It was probably the pos battery cable touching something under the hood while it was loose. I'm gonna try to get it to my shop tonight and see if I can isolate the problem. I'm not a pro with a meter but I do have a pretty good one and hopfully I can fumble through it.

Thanks for your help,
Ray

 

[70_Steve]

One other test... You already hot-wired it by running a hot to the coil, and jumping out the solenoid. Now try turning the ignition switch to RUN, and jumping out the solenoid. If it runs, you've got power to the ignition switch. Your problem is in that Red/Black tracer wire that goes to the solenoid. Or... could be a bad ignition switch, not making contact at the START contact.

Lots of stuff to look at....