Guys, I just now remembered something. Back in 1985 I was running a civi K-20 diesel on my hunting trips out west, and on one particular return trip from Wyoming to Georgia, my 6.2 diesel began to sputter on I-70 in Kansas so I pulled into a truck stop around 3:00 a.m. My fuel gauge did not indicate that I was completely out of fuel, but it was low enough that I needed to fill up anyway. I pulled up to the pump and cut her off. After filling the tank, the truck would not re-start. I would crank for 10-15 seconds, then let it rest for a few minutes, then try again, but after several of these episodes, I realized that something had to be wrong. So I went into the truck stop office and asked if they had a mechanic there who could troubleshoot the problem. They did, and out came a tow vehicle to pull my truck into the drive-through truck repair bay. The mechanic was an old arrogant fart who didn't say much. After fooling with it a few minutes, he pulled out the check valve on top of the injection pump. He then said, "here's the problem". The check valve was stopped up in the closed position. It would not allow a sufficient fuel flow to come through the pump. Because it was after 3:00 a.m. on a Sunday morning, and the chances of getting a new check valve were slim to none, I watched him take check valve over to his vice and drive a 16-penny nail through it and bust out the glass ball. He then blew it out with his air hose and replaced it back onto the top of the pump. The truck cranked perfectly. I paid the $15 service bill and continued on my way.
So before you go to the extent of replacing the pump and injectors, take a look at that check valve. If it is stopped up and preventing or restricting the flow of fuel through the pump, that just might be your problem. The check valve is Model #23183 from Stanadyne and they are regularly on Ebay for around $30. You might want to do a search on there. I have a new spare I keep in my tool box.
Hope this helps.
