Gulf Stream macerator

[Chubbiegull]

Pump is working. At least it sounds so. Valve open to outside. No discharge. Suggestions please.
Thanks in advance

 

[dstarok]

I had a similar problem due to a cracked Y valve on suction side of pump.

 

[ROBERTH]

I had a defective ball cock valve. The stem from the handle to the ball was corroded from electrolysis. When turning the handle, the ball remained closed.