I have just replaced my 2 hp sprinkler pump and all of the line leading from the ground. I did replace my check valve. I cannot get my pump to prime. I did check for air and I did fill the pump with water. I have done this before with no problems except for changing the check valve. Any thoughts.

An air bleeder port between your check valve and pump? Is the check valve installed in the correct direction?

Yes, the arrow points up. For some reason it took over three hours to prime and is working good. Have not lost the prime in two days.

Thanks