NOTE
No individual parts are available for the inlet assembly. So if you do take it apart for cleaning, be careful not to lose any parts or you will have to purchase the whole assembly.
Question: How do you know when to replace this part?
Answers:
1: If you lost any parts inside the assembly you must replace the assembly. (The most common part to lose is the ball, which cannot come out on it’s own. If it is lost it means the user took the assembly apart and lost the ball.)
2: An inlet will eventually wear out and need replacing. A worn inlet will give you similar symptoms as a worn packing. So it is sometimes hard to tell when to replace the inlet assembly. The basic way to tell is if the pump is priming, but will not build up full pressure. And if you know that the packing is good (and that the upper and lower ball is not stuck) then replace the inlet assembly.
Check your manual for application if not listed.