Cummins Engine Swap no start - HELP Needed
 

Hello, I swapped a non-53 block Cummins in for my 53 block that had cracked. Both engines are 1998 model 24V Cummins engines. Everything else was carried over and plugged in. Now engine cranks, but will not start. There is no 'Wait To Start' light on dash and no manifold heater or lift pump engaging. All fuses, connections, and grounds are good. Any help would certainly be appreciated. Again, the issue is there is a no start on the lift pump and manifold heater, so she cranks dry. Thank you.

If you had the injector lines off or loos you need to bleed them before you try to start it, you can also try unplugging the main connector on the VP pump, it will idle without being plugged in

Possible relay problem? The lift pump isnt coming on, what if you hook it to a battery?

Definitely sounds like a relay is not working or being triggered, if you have the early single connector for the main wiring harness you will want to find a larger red wire with a white strip, hook up a test light to that wire and turn the key on, That is the main power source that turns on the computer on the engine, if your test light does not come on there is definitely an electrical issue.
It will run without power to the computer, there is another wire that turns on a solenoid on in the injector pump, that is what is keeping your truck from running I'm guessing.
The first thing I would do is check all the fuses, and wiggle all of the relays in the fuse box