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That check valve has a cracking pressure much higher than that centrifugal pump could hope to draw when it's dry and probably just sufficient when primed. I have modified that type by cutting back the spring in gradual steps until I had just enough to close it when at rest but if someone in the future replaces it they will have to do the same thing all over again.
If you need to have it, and it looks like you probably do, a far better solution is to install a swing check valve in the line instead, they rely on gravity to close a flap instead of a spring driven plunger and way less cracking pressure. You will still probably have to prime it the first time though.
That hose used for the line is not the correct type either and should be replaced. That is vacuum hose and not rated for below waterline use, replace it with some good quality wire reinforced hose rated for suction. Black rubber hose will also grow less crud inside compared to the clear vinyl you have now.
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