That's certainly a possibility. If you uncouple the QD's from the loader and hook them together at the hydraulic pump that will take all the components out of the system and allow the fluid to cycle through the pump without deadheading. Provided, of course, that the QD's themselves are sealing/coupling properly.
If it turns out that one of the QD's is not working right you can either by better aftermarket ones like Prince or you can simply remove the check balls from the existing ones. That would mean they no longer would shut off when uncoupled, but that's not really a problem since when you disconnect the loader you couple its hoses to themselves and likewise for the hydraulic pump hoses.
If you discover that on of the connections has come apart enough to let the check ball close, I'd strongly recommend replacing them all. In the meantime, you can re-couple them and use either stainless steel worm-drive hose clamps or even heavy duty zip ties to act as safety locks on the joints.
Let us know what you discover.
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