It's easy to overlook. AMK Products makes an (expensive) exact reproduction of the Motorcraft solenoid. In the box is a note warning that unless the solenoid mounting points are cleaned down to bare metal and the solenoid securely mounted, there won't be any warranty coverage.

 

Something is not adding up. It's really odd to me that you heard the solenoid click at all if it was not grounded properly; the "click" you hear is from a metal plate shorting the two contacts together. If the solenoid was not grounded, you wouldn't hear a click at all because there would be no current through the relay coil. Also note that dielectric grease is non-conductive (dielectric is another word for insulator). As such, greasing the bolts as you did would not have actually improved the connection.

I don't want to burst your bubble if it's back up and running, but just something to keep in mind if it acts up again. You might have an intermittent solenoid that could fail again. When I walk away from a problem, I like to have a complete understanding of what happened and why what I did fixed it.

 

Nah I totally agree, I always try to flesh things out.

I can tell you that it was working fine up until a few days ago, so it may well have still been receiving some negative voltage (enough to make it click?). I did brush some thin but noticeable corrosion off the screw heads, the contacting inner faces, and when I reassembled everything, it cranked right up, and did so several more times.

It is definitely strange to me that the solenoid was still able to deliver 12 volts to the output post with the key in start, but that that didn't turn the starter over. That indicates a working solenoid I would think?

I will say, I haven't paid any attention to the electrical contacts up front there for over a year. I undid, cleaned, greased, and redid all the connections (besides the solenoid mount) with no effect. Then I went through the solenoid mount and it seemed to do the job. Could I have initially been having contact issues at the starter, tweaked the solenoid just enough to fully break it's ground in trying to figure out the issue, fixed the other contact issues, and still blamed it all on just one problem? Sure, but I can't know that. I've never had reason to believe that it's been the solenoid itself that's broken, it's given me twelve volts at the output every time I've tried it in this recent issue, but it could've been the problem all along. I carry a spare, but I never saw reason to change it this time.

I would love to know exactly what's going on, but I'm switching to a diesel soon, it's not worth it to invest in new wiring for this engine, and up until this point, I wasn't smart enough to. I've been working for myself, full time as of this summer, and the importance of preventative maintenance has been one of the biggest lessons. Whether it's making sure my tools are always together and ready, even if I don't think I need them in the morning, or doing what I can to be sure my old truck will start tomorrow, even if it will today. I always felt that I should flesh out a problem to it's bitter end, but when the money is out, and the sunlight's quick to follow, it get's to be a tougher argument. One I'm teaching myself to push through every day though, as mentioned.

Thanks for all the help, hopefully breathing a little life back into some combination of these contacts will do the trick for a long time down the road. If not, I'll try the other solenoid, and if not that, well, hopefully I'll have found a cheap diesel by then. Here's to a Christmas wreath on all of your grilles! Just put mine on today! AleX