Possessed Pickup starts w/o key after new starter!

[fordhombre]

Replaced the starter on my '69 f-100 w/ a 351w. All was well.

I also replaced the solenoid and rubbed dialectic grease over all connections. I'm pretty certain I connected everything correctly to the solenoid.

So, I connect the battery back up, and get ready to crank. It turns over just fine. This new starter sounds different from the other one but the engine ROARS to life, sounding very eager to go. I was really pleased.

Then I kill the ignition, and try to start it right back up again (this is where the old starter struggled). It started fine, but continued to try and start even when I let the ignition rest into the ON position. So I turned the ignition OFF and pulled my key out. It was still turning over and over and over. I ran and grabbed my wrench and disconnected the battery. That finally put it to sleep.

So, I guess my question is... where have I gone wrong? And why did it only do this the second time I tried to start it, and not the first?

I'm thinking I could've either:

A> re-connected the wires wrong, crossing the ignition w/ the battery (though i thought they were SUPPOSED to be connected)

B> this was a pre-existing problem but the old starter was maybe too worn to malfunction? (unlikely)

C> Something i didn't think of and you great guys will suggest.

I'm off to check keith's schematics now. Thanks in advance for any help!

[fordhombre]

okay, by solenoid, i've been meaning the starter relay tucked under the hood on the left side there. And i think that is my problem.

I used a multimeter to do a continuity check between the four prongs, and all 4 had continuity to the first (from the battery). So I'm guessing this thing just opened up on me???

I checked continuity on my old relay and they do NOT connect, so that would certainly do it.

Taking the relay back now, hopefully for a better product.

[Thunderfoot]

Yep, sounds like a bad starter solenoid... I had a brand new one do that exact same thing to me a few years back.

[fordhombre]

Yeah, I exchanged the relay for another and now things are golden. The pickup now starts so quickly if I hold the key over for more than a millisecond, it will grind the flywheel!