julianfoulger

The system is at circa 450 psi so if there is a leak, it really should show itself fairly quickly once pumped up to circa 450psi. If the car is stored in a dry garage, it should show itself on the garage floor (although the fluid does dry fairly quickly). It could be losing fluid at the pipe junctions, pipe to spheres, Schrader valves, or the rubber membrane in the spheres.

PS: In my experience, the pipe connections should never be over-torqued and indeed there is no need as the seals (like aircon seals) are very good. The valves within the Schrader casings (same type as in bicycle wheels) can be replaced (just purchase the tool which is a couple of quid off eBay or a bicycle shop) - sometimes they just need to be tightened.