I read the other thread about the 72 won't start hoping it would help me get my 71 to start.

302 engine.

My brother and I bought this for 675 knowing it needed work. After much tinkering.... New plugs, wires, dis cap, it was still running rough. My brother took the 2 barrel carb to work and his buddy rebuilt it. Slapped it back on and it was running great. Drove it for several days, no problems. We changed the front brakes, then it would not start. I got it to start, but I did so by turning the ignition only part of the way. It would just keep spinning over if you turned the key too far. Brother took it to the gas station, couldn't get it to start. I went down there with jumper cables and slowly tuned the key and it started.

A few days later, thinking that it was ok to drive. My brother drives it to work. 27+ miles. He said it started running rough but made it.

After work he calls. On the side of the road 1/2 mile from work. After many attempts, it shoots gas out of the carb. One more try, it starts. Only runs 30 seconds. Sounded good. In time. Couldn't get it to start again.

Tow it home. Change coil. Check for spark. No spark from coil, old or new. We did get a very weak spark from the coil wire once, but never got one again.

Where do we go from there? Had jumper cables on the whole time. Changed ground wire on battery.

 

Oh yeah, we changed the ignition switch too.

 

Check the power wires coming to the coil. There should be 2 positive wires; one is full time power when the switch is on, but it should have a resistor in the harness that cuts the voltage down to about 6 volts so it doesn't fry the points. If it has a full time 12 volts, somebody removed the resistor and it's probably frying the points.

The other wire should be coming from the starter solenoid. There are two small prongs on the solenoid, and the rear one gets a signal whenever the starter is engaged that provides a full 12 volts to the coil, but only when the motor is being cranked to give it a short burst of extra spark to help it crank up.

 

My brother changed the points but did not set the gap. Set the gap at .019 and it fired on the first try. I keep running inside to look stuff up on the internet, relaying the info, and trying until it started.

I guess that's what you do when you have 2 rookies trying to fix a problem.

 

Okay...just for you rookies, just so ya know...leaving the key on in these old trucks sends current through the points and helps fry them down. They were probably due for a change...sounds like a tuneup is in your future.