I am replacing the manifold of my DE filter (Pac-Fab Nautilus FNS SS). The old manifold has cracks everywhere and a bunch of D.E. was blown back to my pool. Anyhow, I am having trouble attaching the air strainer to the manifold. For some reason the air strainer can only be attached to the manifold loosely and I am afraid that it will be blown away once I turn on the pool pump.
One strange thing that I noticed is that on my manifold, at where the air strainer should be attached to, there is small piece of plastic sticking out, preventing me from pushing the air strainer all the way down. This is really strange to me since I got both parts from the local pool store and they are compatible parts from the Pentair catalog. Am I missing something? Is it supposed to be loose fit between the air strainer and the manifold? Please advice if you know anything about this, I truly appreciate all your help.