The continuing saga that is the Expedition expedition:
Finally got it all back to one piece on Saturday, but didn't start it. Sunday, I checked all fluids one last time, and turned the key. It started fine, but didn't sound right. However, when I put it together, I didn't fill the torque converter, so I knew that the transmission would have to pump it full before I could top off the ATF, so I "write it off" as transmission-pumping-noise. I let it run for a brief time, and then checked and topped off the ATF. Then, I attempt to restart it, and the starter motor spins, but without the starter gear extending. So, I take a lunch break. Afterwards, I pull the starter and head to O'Reilly's for a replacement (it was replaced in 2015 with a new house-brand with a lifetime warranty).
After returning, I installed the new starter, start it up. Still sounds odd. I shut if off immediately. Check ATF level (fine), and re-start. Or not. Same thing. This time, instead of taking a break, I immediately investigate. The engine is still room temp to the touch, but the starter is smokin' hot. Blaming it on crappy store-brand parts, I return to O'Reilly's (it's a 40 mile round trip from the boonies), and get a third starter. I get back, go through the same routine. And for a third time, it won't start a second time, with the same symptoms. This time, I notice that the solenoid is smokin' hot, but the starter motor itself is just warm. At this point, I decided to remove the third starter, put up my tools, and call it a weekend.
At lunch today, I ran over to O'Reilly's to get a fourth starter, but I will do a ton of diagnostics before I install it this time. It appears as though the solenoid is staying energized after starting is complete. I think that was the odd sound I was hearing. I also picked up a new battery (actually, my wife did), as the old one load-tested marginal, and I don't want to worry about it. My plan is to replace the battery cables, since they are 21 years old and not in the best of shape, clean all ground locations, replace the starter relay, and then check continuity/resistance/voltage drop on all lines in the starter circuit, including checking for shorts to ground or battery-positive.
For those keeping tabs, here's a list of the components replaced so far:
Torque Converter
Transmission (Rebuild)
Transmission Dust Covers
Engine Long Block (OEM Ford Reman)
Fuel Injectors
Thermostat
Coils
Intake Manifold
Vacuum Fittings
PCV Valve and Elbow
Front and Rear Driveshaft U-Joints
Front Shock Top Mount Isolators
Fuel Filter
Fuel Pump and Gasket
Transfer Case Shift Motor
A/C Accumulator/Dryer
Transfer Case (Rebuilt by me)
Front Body Mounts
Heater Hose Connectors
Serpentine Belt, Idler, and Tensioner
Idle Air Control Valve and Gasket
Hood Lift Supports
License Plate Light Bulbs
Radiator
Lower Radiator Hose
Added Backup Camera
Added GMRS Radio
Starter
Battery
Oh, the joy of reviving old vehicles. I just want to finish this project so that I can start on the LJ! My mood is better today. Yesterday afternoon, I was not pleasant to be around...