Alright. So I'm about ready to set the F-350 on fire again. Ha. For some reason, unbeknownst to me, the truck is not charging. It's an '85 F-350, 460, 4-speed, 2wd, CC/LB. On my way home from work this past Friday night, I stopped to get gas. I shut the truck down, put gas in it, and went to start it up and leave, and the battery was dead. I got a jump start, and it ran just fine on the way home. When I got home, I went to start it again, and it just clicked, indicating a dead battery. So, I pulled the battery out, put her on the trickle charger and went to bed. I got up Saturday morning, put the battery back in the truck, and she fired right up. By the time I got to work at 3, the battery was dead again, but it'd jump right off. So, I figured that the alternator was bad, and had my buddy go pick one up. I changed the alternator in the parking lot at work, jumped it off, and it still wasn't charging, as I could watch the headlights get dimmer and dimmer, but I got on the road and tried to make it home. She died on the way home, and I pulled into a gas station. I had my buddy run me home to get another battery, came back, swapped batteries, and she fired up and I made it home. When I got home, I shut it down, and tried to start it again, and the battery was dead. So, I put it on the charger, and drove to and from work Sunday and yesterday on the battery. This morning, I got up and went back to O'Reilly's and got a voltage regulator, got home, put it on, and it still isn't charging. Went back with the alternator, and had them test it and it tested bad, so they swapped it out. I got home, put the new alternator on, and it still isn't charging. So now, I'm stuck, I have no idea what's going on with the truck, all the parts places are closed and I'm clueless.. There's good tension on the belt, all the wires are hooked up according to my 1983 FSM, I've been through two alternators and a voltage regulator and she's still not charging.. I hate to say it, but I'm fresh out of ideas.. Am I missing something here? Anybody have any ideas?


Thanks, guys.

 

Get out a multimeter. You have a parasitic draw?

Or more likely, what condition are your straps in? Especially ground.

 

All the grounds and everything look alright. According to Advance's tester, the battery never reads above 12.3 volts while the motor's running, regardless of engine RPM. I had a multimeter a long time ago, but I believe it's become lost over the course of the past four or five moves.

 

If the battery voltage never gets above 12.3 volts you aren't charging. When I had an alternator go out it took the regulator or vice versa. I had to replace both the units at the same time to get it working.

However, is an '85 a G1 or G2 alternator? The latter had connector problems.

 

It's not charging at all. And, I've replaced both the regulator and the alternator. I've put two alternators in it, and it's still not charging.

Unfortunately, I have no idea whether it's 1G or 2G, or how to tell the difference.

On the upside, I did find my handy dandy multimeter. So, armed with that and my FSM, I'm going at the charging system head on tomorrow evening. I just hope I can make it back and forth to work between now and then. Haha

 

He says he has replaced the regulator, so I would assume he means a separate regulator (1G style)
It takes power to make power.
Use your multi-meter and check that you have voltage getting from the F (field) wire to the alternator with the key in the 'run' position.



Could be the ignition switch or an open circuit anywhere between the switch and the alternator

 

Well, first I suppose you should check to see that power is getting to the regulator through the green/red wire.

It appears that "hot in run" going through the charge lamp is fused.

 

Good point - if he replaced the regulator it is separate and, therefore, a G1. Duh!

 

You can change the regulator on a 2G. It's simple enough.

But since he said he had changed the alternator first, and then changed the regulator, I assumed he has a 1G.

I would definitely check for power into and out of the regulator with the key on.
And check for possible resistance or open in the alternator's ground wire.

If the fusible link is burnt it should be apparent.