I have a 70 Challenger 383 that I'm restoring. It has a starting problem. I turn the key and there's nothing. But if i leave the key on and jump the starter relay it starts. Can someone please explain what I need to do. Thank you.
First, im assuming that when you say "there's nothing" that you mean there is no cranking.
There are two wires at the bottom of the starter relay..
One is ground that comes from the transmission to insure that it is either Neutral or Park. No Ground and the relay will not activate. Verify that you have ground !! That is number one.
Two, The other wire comes from the key switch when key is turned to start. So, with someone turning the key to start, verify that that wire has 12 volt power. If both power and ground is there, then the relay is bad. If missing either check which is missing and find out why. Examples If no 12v then could be...bad starter switch, or bad connection at bulkhead connector, or at the connector right at the steering wheel. If no ground, then then it could be the neutral safety switch at the transmission. Or severed wire, etc.