84 300SD starts fine cold, will not start warm

[clangrant]

Weird problem. This car sat for a year with a broken lock cylinder. Finally got it fixed, car started fine
However, if you start it, let it run for even 1 minute, then kill it, it will not restart unless you let it sit for 30 minutes. I have changed all fuel lines, all fuel filters, cleaned the tank, new glow plugs, new glow plug relay, new air filter. Nothing I have done helps. The problem never gets worse either, though. Any ideas? This is driving me crazy.

[Flatlander1961]

I worked on some older diesels 25 years ago and we had one with a similiar issue that was solved by having the diesel injector pump timed properly. It was off by 1 degree or less. I am not fluent enough in Diesel lore to know if this could even be an issue at all with yours. I am also wondering what might expand with heat and prevent you from starting?

[clangrant]

Well, turns out the last person to work on the car, oover a year ago, reversed the vacuum lines on the ignition switch, so once the car generated any vacuum, it held the vacuum on the back of the injection pump, thus car would not restart. After exactly 30 minutes, enough vacuum would bleed off and car would restart. I reversed the hoses and car starts like its new. It should though, after all the fuel work I have done on it.

LOL