Claim missing equipment, hydraulic switch after acceptance

The fulfillment claim against the general contractor expires.

So yes and no. A defect can still occur after acceptance. If it was not known at acceptance that the hydraulic separator was missing, then it can hardly be assumed that it was accepted as is.

It is true that the burden of proof now lies with the client. A missing separator is strong evidence that it simply was not delivered. I would be optimistic about winning the case.