'75 F-350 won't start
 

Need some help. I have a 1975 F-350 dump with a 390 ci engine. I've changed the solenoid and the starter and have charged the battery but when I turn the key, the solenoid just clicks. I've cleaned all the electrical connection from the battery to the starter. Never had this much trouble getting a Ford to crank.

Do you have any provision to hook up a jumper battery? If you do try and see if it makes any difference when trying to start. Not knowing what equipment you have available to test with, I have to be certain the battery is good and the charger is working .
After that are you able to at least move the belts and see if the engine is free to turn.
I don't remember if they used two solenoids in the starter system on those older bigger engines. Sometimes the solenoid will pull in when energized , but not well enough to send enough current to the starter for it to operate. With a test lite confirm that you are getting voltage down at the starter itself.

Thanks Hanky. I took the battery and had it tested today and sure enough, it was bad. This truck has an electric dump on it and it worked fine, so I thought the battery was good. I had tried jumping it as well, but it wouldn't start that way either.

If you still have the no start condition, do you know if you are getting spark to the spark plugs?

Thanks hanky, but the new battery did the trick.