Oil pressure drops out after 30 seconds of run time

[Tazman85305]

I have an 04 Dodge 2500 that has had an engine swap to a 6.7L, using the 5.9L fuel, air, and valve train systems.
It has been running great for 4 years.
This week, about 30 seconds after start-up, the oil pressure guage drops to zero. I replaced the oil switch, yes I know the guage on the dash is for show, and got the same results.
I installed a mechanical guage on the filter housing and it reads zero pressure at start up. When I disconnect the mechanical guage, there is zero oil present on the quick disconnect.
Open to suggestions....

 

[H3LZSN1P3R]

I have an 04 Dodge 2500 that has had an engine swap to a 6.7L, using the 5.9L fuel, air, and valve train systems.
It has been running great for 4 years.
This week, about 30 seconds after start-up, the oil pressure guage drops to zero. I replaced the oil switch, yes I know the guage on the dash is for show, and got the same results.
I installed a mechanical guage on the filter housing and it reads zero pressure at start up. When I disconnect the mechanical guage, there is zero oil present on the quick disconnect.
Open to suggestions....

Sounds like it may be a bad pump or the pickup screen getting clogged. Do not run it with no oil pressure