This urgent since my 69 (390) is parked on the city street. Son-in-law started it up went to 7/11...got back in and everything was dead. I drove over and I had power to lights it seemed like low battery. I changed batteries and tinkered around and she started...daughter let it warm-up and she drove down the street and it died. This usally happened when it cold (manuel choke). I couldn't get it to turn over al all, it's like I removed the battery. I checked the cables and I have power accross the poles, and accross the starter relay. So I assumed it was the switch. I replaced that still nothing. I again assumed it was another weak battery jump it from my other ford and nothing...I found some fuses under the right hand side of the dash (two large and three small ones) they seemed ok (visual inspection)..I follwed the (what appears to be the hot lead from the relay and found an in0line fuse, and it was fine...god not sure where to go now... truck lights come on (weak) and so does turn signals...any ideas where to go now? Tow home and tinker or drop off at grage...HELP!!

 

It sounds like you may have a parasitic draw Lonnie. It's a symtom where something is having a draw even when everything is seemed to be turned off. I would like to know when does this occur? Right after you shut the engine off? Test the alternator at your local shop for an amperage load test first to see if your alternator is actually charging properly, then what I would do is look for a parasitic draw. It cood be a short to power or ground or a dirty switch. Heck it could be alot of things in a truck this old. An easy way to do a basic parasitic draw test is to disconnest your posotive cable only and get a voltmeter and put it in milliamps mode. Then put one lead on the posotive post and the other on the posotive lead. You should not get a reading above 50 milliamps, if you do then start unhooking stuff and see if it makes your reading go down.

 

I'll give it a try...I do have a new engine in her and this just happened for the first time today. Just got in after a short drive down the road...and bang nothing..

 

Check the plug under the passenger side of the dash. There is a wire that goes from the starter relay to the ignition switch. Could have worked it loose.

 

Sounds like bad ground to me. Try putting both legs of your jumpers on the ground side of battery. than put one leg on engine close to starter and the other leg on boby. Like fire wall.

 

Yeah it does sound like a bad ground. Check or replace the battery cables and get the alternator and the battery checked. Good Luck

 

yeah to run like that then stop when I have power does strike me of a ground or loose wire...not sure where that "plug under the passenger side of the dash" is I assume inside...but what is it?.. I don't understand this...could you explian a little more about this procedure"Try putting both legs of your jumpers on the ground side of battery. than put one leg on engine close to starter and the other leg on boby. Like fire wall" thanks...with the truck along side of the road I'm getting despraite..don't want to tow it if it's just a loose wire or somthing simple..

 

Basically check all your grounds. take neg cable of the truck. Clean both ends so they are shiny. Check engine to frame and engine to fire wall. clean the ends or replace them. The test with the jumper cables was just to test your grounds.
do not hook cables to another rig this way. No test will work if the connetion at the battery is bad. If you have the battery cables that clamp to the cable with two 7/16 bolts throw them away and replace with new cables.

 

Once you get home and have all terminals cleaned up add a conductive anti-corrosion compound like KOPR-SHIELD. It is made by Thomas & Betts, available at a good electrical supply house. Works good on battery terminals and lamp contacts as well.

 

i had that happin to my 69 f250 too.the regulator stuck and put a 12 volt draw on the batt.check the chargeing and see if the regulator is stuck.it will sap the batt down fast.

 

Good call 1949f1 I had forgoten that.

 

Ok, I cleaned the battery, replaced the cables, replaced the switch, and the starter relay...nothing.. I can crank it over if I bypass the starter relay using two screwdrivers...but when I just trun the key I here what saound like a spring going "boeing"..weird...anyother ideas?

 

oh to add to the mess...I have power to the lights turn signals. This sure has me guessing

 

by starter relay. Do you mean the starter solenoid?

 

well it's the one on the fender wall...close to the battery..power coming in and out the other side...