Starting Woes.

[wheeble]

My 1971 F100 has had intermittent starting problems for a while. After replacing the starter, had same problems. Not enough juice in battery to turn the starter if the truck sits 2 days. I then replaced the alternator as it checked bad on the bench. Got a new one for $11 bucks. Same problem continues with starter. Found solenoid was bad so replaced that too. Still got problems. Replaced ignition switch, same problem... Finally bypassed the ignition switch wiring by installing a start button direct to the selenoid, now when the key just clicks, I hit the button and it fires right up. So I have concluded there is just too much resistance in the old harness for the starting system to work unless the battery is at 100%. At some point I will replace the harness, for now the button will do. Cheers, hope this helps others with similar problems.

[sargentrs]

Necessity is the mother of invention! Had a similar issue with my '74 Dodge Dart, notorious for electrical problems. Wired a toggle switch for ignition power and a push button for start. Flip the switch, push the button and drive. When I parked, flip the switch back off to kill her Drove it like that for a couple of months until I traced it down and fixed it right. Remember, our solenoids are bad about being faulty right out of the box. Grab a voltmeter and start tracing the circuit from the battery backward, checking for voltage drops. Just went through this on my '64 Fairlane. Battery never gave me a problem until I had her parked for a couple of weeks while I resealed the engine. When I went to start her back up, the solenoid would just buzz. Replaced the solenoid but it just clicked. Put a voltmeter on the battery and got 12+ volts. Moved the lead to the terminal on the end of the cable and only had 10.8v. Cleaned the cable ends and got 12+. Turned the key on and only got 10.8 at the solenoid where the battery cable connects. Turned the key to start and the voltage dropped to 5v. Replaced the battery and she fired right up and have had no issues. Your problem could be anywhere and anything between the key and the starter. Systematically check voltage at all connections watching for the voltage drop.

[wheeble]

Thanks for the reply.
Yep, electrical gremlins are a pain in the a$$. Everything in the system is working correctly except as I outlined above. The wiring under the dash and in the engine compartment is all original to the truck except for a few runs I have made, and is very brittle. I peeled back some insulation here and there to check for corrosion and found most of the wiring is oxidated and powdery throughout. (makes me think the truck went swimming at some point). A new harness is definitely needed.

[sargentrs]

I feel your pain! I bought one of these to rewire my truck. Comes with generic/GM connectors but quality is excellent. Probably splice in my old switches. Haven't gotten that far in my project yet but can't beat it for the $$.http://m.ezwiring.com/site/store/viewit ... d=4&imz_st