So you learn something new every so often. As I posted above, I had issues with the fuel shut off solenoid. Having tested (and two other people) the wiring and getting the correct voltage going to the correct wires when you turn the key to either run or start, everyone figured the solenoid was bad. I ordered a new one online, getting a heavy duty version that fits in the stock location. It arrives and I go about installing it.
First interesting issue I came across. In the Dodge Ram version of the Cummins engine, the solenoid uses a 2.5" mounting spacing. On larger truck version of the Cummins, they use a heavier duty version that uses a 3" mounting spacing and weighs about a pound more. Apparently a previous owner changed out the stock mounting bracket and installed the larger version. I bought a solenoid that uses the heavy duty part but mounts with the 2.5" mount. Yep, my new part did not fit the non stock bracket. Hummm... that's a problem. I went to NAPA and they were able to find the same solenoid I had but it's a special order and $616. WOW!!! The one I had cost me $150. The company sells the stock bracket for $20 so I figured Monday I would order that.
So I started reading more and is seems that the heavy duty version almost never goes out. Hummm... interesting. So I took the "bad" solenoid and pulled the wires out of the plug and jumped them onto the battery terminals. CLICK It works! Okay, this is a wiring issue but I am showing power at the connectors. There was some corrosion where the fusible links connect to the battery. I cleaned everything up and tried again. Still no go. Well, the one other part that can go out is the relay but that seemed to work as the test light would trigger with the key.
When I bought the solenoid I also ordered a spare relay. I plugged that in and the solenoid worked perfect!!! Awesome. So what did I learn? Wires can show voltage when testing but not current. This solenoid pulls about 55 amps during start up and the relay wasn't allowing the current to pass. Can't say I have seen a relay do that before.